book of abstracts frank harris -...
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Book of Abstracts
Concepts of Mathematical
Physics in Chemistry
Workshop in honor of
Frank E. Harris
Iberostar Quetzal,
Playa del Carmen, Quintana Roo, México.
Dec. 10-12th, 2014
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Welcome message
I am delighted to welcome you to Playa del Carmen, Quintana-Roo, México and in particular to
the Iberostar hotel resort for the workshop “Concepts of Mathematical Physics in Chemistry” in
honor of our dear friend and colleague Prof. Frank E. Harris. This meeting brings together
experts and scientists, but most of all, colleagues and friends.
As you can see from the book of abstracts, the meeting includes more than 30 talks in mainly six
areas of research:
1. Mathematical physics
2. Electronic structure
3. Density Functional Theory (DFT)
4. Collision dynamics
5. Nanostructures & confinement
6. Experimental physics
Of course, we are delighted to have our honored keynote speaker Prof. Frank E. Harris
We hope that you will find the conference, the scientific program, the gathering of scientific
colleagues and the venue both valuable and enjoyable.
Dr. Remigio Cabrera-Trujillo
On behalf the organizing committee.
ICF-UNAM, Cuernavaca, Morelos, México
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Local organizing committee: International committee:
Remigio Cabrera-Trujillo, UNAM Remigio Cabrera-Trujillo, UNAM
Salvador A. Cruz Jiménez, UAM-I John R. Sabin, UF
José Ignacio Jiménez Mier y Terán, UNAM Neil Sullivan, UF
Antonio M. Juárez Reyes, UNAM Henk Monkhorst, UF
Ricardo Méndez Fragoso, UNAM Jens Oddershede, SDU
Alberto Vela Amieva, CINVESTAV H. F. Schaefer III, UG
Joseph Fripiat, Namur
Ryan Chancey, TX
Sponsors Institutions
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Frank E. Harris; a name to be reckoned with! It is with great pleasure that we hold a symposium in honor of Frank E. Harris in celebration of
his eighty fifth birthday. Frank is an internationally known quantum chemist and physicist who,
since 1969, has been Professor of Physics and Chemistry at the University of Utah. In 1998,
Frank was appointed Adjunct Professor in the UF Quantum Theory Project and Department of
Chemistry, and has been a Visiting Professor of Physics during that time. Recently, he has been
made Research Professor.
Frank’s work has provided pivotal contributions to modern computational quantum theories,
motivating a new generation of students and fellow scientists. He has, in particular, worked
extensively in quantum chemical determination of the properties of molecules as well the formal
aspects of quantum chemistry. He is especially recognized for his work in introducing the formal
mathematics of physics into theoretical chemistry. Frank was one of the earliest investigators to
implement the use of Gaussian basis sets in quantum chemical calculations,1 which has become a
standard method in the field. In addition, Frank has published several books, both for teaching
and research. Arfken, Weber, and Harris (2013), and a textbook entitled “Mathematics for
Physical Science and Engineering - Symbolic computing applications in Maple and
Mathematica” (2014).
The scientific record that Frank Harris has made, and continues to expand, is impressive. His
work in formal and molecular quantum mechanics is attested by his long list of research
publications and invitations to speak at meetings and universities, around the world.
Frank has visited many universities and labs, including the University of Florida, many times
each year. In each case, he has worked and published extensively.
Internationally, Frank is also well known and is primarily associated with the Universities of
Florida and Utah. He also has close connections with the University in Namur, Belgium, where
he has organized a symposium.
Frank has had a long and productive career. He has had a positive influence on University
education, and is an internationally recognized scientist.
John R. Sabin
Gainesville, FL, 2014
1 “Gaussian Wave Functions for Polyatomic Molecules,” F.E. Harris, Rev. Mod. Phys. 35, 558-569 (1963)
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PROGRAM
Registration/Reception: Tuesday 9th
, 17:00-19:00 Salón Oaxaca
Banquet: Wednesday 10th
, 18:30-20:00 Mexican Restaurant
25 minutes talks + 5 minutes for questions: All in Salon Yucatán
TIME Dec 10 Wednesday Dec 11 Thursday Dec 12 Friday
8:00-8:30 Chair: Cabrera-Trujillo
Opening J. R. Sabin
Chair: R. Méndez-Fragoso
O12 John Mintmire
Chair: J. Recamier
O24 Benoît Champagne
8:30-9:00 O1 Frank Stenger O13 Rodrigo Morales-Cueto O25 Henry Scheafer
9:00-9:30 O2 Eugenio Ley-Koo O14 Samuel Trickey O26 James W. Dufty
9:30-10:00 O3 Joseph Fripiat O15 Andreas Köster O27 Antonio Juárez
10:00-10:30 O4 José Recamier O16 Irineo Pedro Zaragoza O28 Xiaoguang G. Zhang
10:30-11:00 COFFEE COFFEE COFFEE
11:00-11:30 Chair: J. Sabin
O5 Per Kaijser
Chair: J. I. Jiménez
O17 Yngve Öhrn
Chair: E. Ley-Koo
O29 José Jiménez-Mier
11:30:12:00 O6 Barry Schneider O18 Keith Runge O30 Salvador A. Cruz
12:00-12:30 O7 Carlos Bunge O19 Fco. Javier Domínguez O31 Hendrik J. Monkhorst
12:30-13:00 O8 César Almora-Díaz O20 Jorge A. Morales O32 Jens Oddershede
13:00-14:30 LUNCH LUNCH LUNCH
14:30-15:00 Chair: S. A. Cruz
O9 Herzain Riviera-Arrieta
Chair: S. Trickey
O21 Hai-Ping Cheng
Chair : A. Juárez
O33 Josef Michl
15:00-15:30 O10 Monika Musial O22 Patrizia Calaminici O334Victor V. Albert
15:30-16:00 O11 Felipe Aparicio O23 Ricardo Méndez O35 Bill Koures
18:30-20:00 BANQUET 16 :00 GROUP PICTURE 16 :00 CLOSURE
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Program Tuesday Dic, 9th 17:00-19:00 Registration : Salon Oaxaca Wednesday Dic, 10
th Salon Yucatan
8:00-8:30 Opening
8:30-9:00 A Convolution Method for Computing Schrödinger's Equations on
R3 x (0,∞) (F. Stenger) ..................................................................................................................... 8
9:00-9:30 Angular Momentum Theory in Bases of Lamé Spheroconal Harmonics (E. Ley-Koo) .. 9
9:30-10:00 The use of the Fourier Transform in the Calculation of Electronic Properties of One-
Dimensional Periodic Systems (Jo Fripiat) ................................................................................... 10
10:00-10:30 Non linear coherent states (J. Recamier)................................................................... 11
10:30-11:00 Coffee 11:00-11:30 Frank Harris’ influence on one of his students (P. Kaijser) ....................................... 12
11:30-12:00 Novel Numerical Approaches to Solving the Time-Dependent Schrödinger's
Equation (B. Schneider) ................................................................................................................. 13
12:00-12:30 Recent progress in the variational approach to atomic and molecular electronic
structure (C. Bumge) ...................................................................................................................... 14
12:30-13:00 Selected configuration interaction with truncation energy error in molecular
systems: Symmetric dissociation of water (C. Almora-Díaz) ........................................................ 15
13:00-14:30 Lunch
14:30-15:00 Viable and fleeting molecules containing He atoms
(H. Rivera-Arrieta) ......................................................................................................................... 16
15:00-15:30 Multireference Fock space coupled cluster method for the description of the
dissociation of a single bond (M. Musial) ...................................................................................... 17
15:30-16:00 Application of the Active Space Self-Interaction-Correction Method to Molecular
Systems (F. Aparicio) ..................................................................................................................... 18
18:30-20:00 BANQUET Mexican Restorant
Thursday, Dic, 11th
Salon Yucatan
8:00-8:30 Density Functional Methods for Extended Helical Systems
(J. Mintmire) ................................................................................................................................... 19
8:30-9:00 Photochromic behaviour of bicyclic boranates and TD-DFT calculations (R. Morales-
Cueto) ............................................................................................................................................. 20
9:00-9:30 Quantum Statistical Mechanics with Just One Orbital
(S. Trickey) ..................................................................................................................................... 21
9:30-10:00 Robust and efficient evaluation of hartree-fock exchange
(A. Köster) ...................................................................................................................................... 22
10:00-10:30 The dynamic interaction of the PtSn bimetalic cluster with ethanol (I. Zaragoza) .. 23
10:30-11:00 Coffee
11:00-11:30 Wave-Packet Dynamics and Group Theory (Y. Öhrn) ............................................... 24
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11:30-12:00 Fidelity in Multiscale Modeling: A Frank Assessment
(K. Runge) ...................................................................................................................................... 24
12:00-12:30 Multi-resolution approach for laser modified collisions of atoms and ions (F.
Domínguez-Gutiérrez) .................................................................................................................... 25
12:30-13:00 Inspired by Frank Harris: Recent Developments with the Electron Nuclear
Dynamics and Coupled Cluster Theories (J. Morales) .................................................................. 26
13:00-14:30 Lunch
14:30-15:00 Conformational Electroresistance and Hysteresis in Nanoclusters (H. P. Cheng) .... 27
15:00-15:30 Transition State Search of Finite Systems (P. Calamanici)....................................... 28
15:30-16:00 Excited states of Nonlinear Schrödinger Equation and nonlinear coupling impurity
in a matter waveguide: analytical solutions and their properties (R. Méndez-Fragoso)................29
16:00 GROUP PICTURE
Friday, Dic, 12th
Salon Yucatan
8:00-8:30 Second-order nonlinear optical susceptibilities and refractive indices of organic
crystals from a multi‐scale numerical simulation approach (B. Champagne)…............................30
8:30-9:00 Density Cumulant Functional Theory (H. Schaefer)....................................................31
9:00-9:30 Quantum Effects in Many-Body Systems Described By Classical Methods (J. Dufty) 31
9:30-10:00 A photoelectron spectrometer for measuring angular distributions in photoionization
and photodetachment of positive and negative ions using synchrotron radiation (A. Juárez) ....... 32
10:00-10:30 Electron transport calculated from first-principles complex bands (X. Zhang) ........ 34
10:30-11:00 Coffee
11:00-11:30 Different oxidation states in CrF2 determined by comparison of a ligand field
multiplet calculation and absorption and resonant x-ray emission at the chromium L2,3 edge (J. I.
Jiménez-Mier) ................................................................................................................................. 35
11:30-12:00 The hydrogen molecular ion confined in dihedral angles (S. A. Cruz)……………..36
12:00-12:30 Rules and Experiments for (Super)Conducting Polymers (H. Monkhorst)…….......37
12:30-13:00 Calculation of shell corrections to stopping power from dipole oscillator sum rules
(J. Oddershede) .............................................................................................................................. 38
13:00-14:30 Lunch
14:30-15:00 Excitons and Polarons in Oligosilane Chains: Five Stereoactive Hybrid Orbitals and
Valence Shell Expansion on a Silicon Atom (J.Michl)...................................................................39
15:00-15:30 Dr. Harris or: How we learned to stop worrying and love the Bessel function (V.
Albert)............................................................................................................................................40
15:30-16:00 Statistical Inference with Minimum Relative Entropy: A robust numerical algorithm
employing sinc quadrature (Bill Koures)........................................................................................41
16:00 CLOSURE
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ABSTRACTS
O1
A Convolution Method for Computing Schrödinger's Equations on
R3 × (0,∞)
Frank Stenger
Salt Lake City, UT
The Schrödinger partial differential equation is first converted to a convolution integral equation
(IE), and a procedure is then described for solving this IE by a novel, accurate and highly
efficient procedure developed by me. This extends an approach used previously by Frank Harris
and Bill Koures.
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O2
Angular Momentum Theory in Bases of Lamé Spheroconal
Harmonics
R. Méndez-Fragoso1, E. Ley-Koo2
1Facultad de Ciencias, UNAM, Circuito Exterior, Ciudad Universitaria, México 04510 D.F.,
2Instituto de Física, UNAM, Apartado Postal 20-364, 01000, México, D.F., México
Corresponding author: [email protected]
The background for our contribution to the Workshop on “Concepts of Mathematical Physics in
Chemistry”, to honor Professor Frank Harris, is provided by our recent works [1-3]. In fact, our
review [1] on “Rotations of Asymmetric Molecules and the Hydrogen Atom in Free and Confined
Configurations” contains in its sect. 4 a discussion about the development of the theory that gives
its title to the present contribution. On the other hand, Ref. [2] on “Ladder Operators for Lamé
Spheroconal Harmonic Polynomials” made the identification of three sets of such operators
connecting pairs of polynomials with: 1) the same eigenvalue of l angular momentum, the same
species and with neighbouring complementary even numbers of nodal elliptical cones , , 2) the same eigenvalue l and different species, corresponding to the operators lx,
ly , and lz and 3) neighbouring values of l'=l1, different parities, kinds and species corresponding
to the linear momentum operators p̂ x , p̂ y , and p̂z . More recently our contribution [3] to the
G30 Colloquium on “Rotations of the Most Asymmetric Molecules via 4-step and 1-step Ladder
Operators” combines the use of the 4-step operators of Valdés and Piña [4] connecting the
eigenstates of such molecules with l= 4n , 4n+1,4n+2,4n+3,n= 0,1,2,. .. of species l , y, xz,
xyz, respectively, and vanishing asymmetry distribution energy, with the use of the angular
momentum operators of the set 2) above acting initially on each of the latter eigenstates to
connect with their companion states of other species, and then successively to complete the 2l+1 set of eigenstates for each value of l . Hopefully, our participation in the workshop will lead to further advances in the formulation of the theory.
References
[1] R. Méndez-Fragoso, E. Ley-Koo. Advances in Quantum Chemistry 62 (2011), Chap 4, 137.
[2] R. Méndez-Fragoso, E. Ley-Koo. SIGMA 8 (2012), 074, 16 pages.
[3] E. Ley-Koo. 30th International Colloquium on Group Theoretical Methods in Physics (2014),
107.
[4] T. Valdés, E. Piña. Rev. Mex. Fís. 52 (2006), 220.
10
O3
The use of the Fourier Transform in the Calculation of Electronic
Properties of One-Dimensional Periodic Systems
Joseph G. Fripiat
Laboratoire de Chimie Theorique, Unite de Chimie Physique Theorique et Structurale,
University of Namur, Rue de Bruxelles, 61, B-5000 Namur, Belgium
The implementation of the HF-LCAO or DFT methods for the study of the electronic structure of
stereoregular polymers needs to take into account the existence and the convergence of one-
dimensional infinite lattice summations appearing in the Coulomb and exchange terms.
Generally, the multipolar expansion is used in order to handle the lattice series appearing in the
classical Coulomb terms while the convergence of lattice summations in the exchange is usually
controlled by the rate of decay of the density matrix elements with respect to the cell indexes.
This approach has the difficulty that the lattice sums involved may converge rather slowly and in
some cases it is not possible to achieve satisfactory convergence, not only due to the large
number of integrals that enter in the computation, but also because of numerical instabilities.
A way out of this dilemma is suggested by the Poisson transformation, which permits a lattice
sum in direct space (DS) to be converted into an equivalent summation in reciprocal (also called
Fourier) space (FS). In general, the more slowly a DS sum converges, the more rapid will be its
convergence in FS. However, the FS approach alone only transfers the regions of slowest
convergence to other parts of the parameter space, so the problem is altered but not eliminated.
But these lattice sums can be partitioned, using the Ewald-type procedure, in a DS and a FS part,
both characterized with exponential (rather than inverse-power) convergence.
This Ewald-type partitioning leads, in the DS partition, to integrals similar to those encountered
in the usual molecular computations using gaussian type atomic orbitals. However, the FS
partition produces expressions that can be identified as incomplete Bessel functions. Reasonable
methods for the evaluation of these functions [1] are now available and it has become practical to
evaluate all the quantities arising when stereoregular polymers are treated with gaussian type
basis sets of arbitrary angular symmetry.
This technique [2, 3] is implemented in a code called FT-1D. It also takes full advantage of all
line-group symmetries to calculate only the minimal set of two-electron integrals and to optimize
the computation of the Fock matrix.
The present communication reports some benchmark studies of this code. Our results not only
confirm the algorithmic correctness of the code through agreement with other studies where they
are applicable, but also show that the use of convergence acceleration enables accurate results to
be obtained in situations where other codes fail. It is also found that full attention to the line-
group symmetry leads to an increase of between one and two orders of magnitude in the speed of
computation.
This work would not have made possible without the decisive contribution of Professor F.E.
Harris to the field. He is, with Professor Joseph Delhalle of University of Namur, who recognized
the importance of lattice sums, the difficulty in computing them accurately. It was for me a rare
privilege and a chance of having the opportunity to collaborate with him over the years.
11
References
[1] Harris F. E., Fripiat J. G. Methods for incomplete Bessel function evaluation. Int J Quantum
Chem, 2009, 109: 1728-1740
[2] J. G. Fripiat, J. Delhalle, I. Flamant, and F. E. Harris, J. Chem. Phys. 2010, 132, 044108.
[3] J. G. Fripiat, and F. E. Harris, Theor. Chem. Acc. 2012, 131,1257.
O4
Non linear coherent states
José Récamier, Ricardo Román-Ancheyta, Carlos González-Gutiérrez
Instituto de Ciencias Físicas
Universidad Nacional Autónoma de México
We study the generalization of Field Coherent States to include nonlinear potentials. We make
use of the f-deformed creation annihilation operators and write a Hamiltonian of the harmonic
oscillator frorm in terms of these. Selecting the deformation function we can generate a
Hamiltonian with the desired energy spectra, as examples we consider the cases of a Morse and
Pöschl-Teller Hamiltonians.
We construct the corresponding coherent states by means of two possible generalizations: i) as
eigenstates of the deformed annihilation operator and ii) as the states obtained by application of a
deformed displacement operator upon the vacuum state.
We analize their statistical behavior considering the Mandel parameter, the second order
correlation function and the Husimi and Wigner functions.
R. Román-Ancheyta, C. González-Gutiérrez, J. Récamier, JOSAB 31 (1) 38-45 (2014).
O. de los Santos-Sánchez, J. Récamier, J. Phys. A:Math. Theor. 46, 375303 (2013).
R. Román-Ancheyta, M. Berrondo, J. Récamier (submitted to Physica Scripta).
12
O5
Frank Harris’ influence on one of his students
Per Kaijser
KRI, Germany
Professor Frank Harris has excellent skills in many fields. This paper is devoted to an area, where
Frank has a special talent and where the author greatly benefited from his knowledge during the
three years 1969, 1970, and 1971. This guidance took place during the summer schools in
Beitostølen, Norway and has later not only helped the author conquer some rough terrains but
also given him much pleasure.
13
O6
Novel Numerical Approaches to Solving the Time-Dependent
Schrödinger's Equation
Barry Schneider
Applied and Computational Mathematics Division
Information Technology Laboratory
National Institute of Standards and Technology
100 Bureau Drive, M/S 8910
Gaithersburg, MD 20899-8910
I will describe recent computational advances in the solution of the time-dependent Schrödinger
equation and its application to elementary excitations in ultracold atomic gases and the
interaction of ultrashort intense laser pulses with diatomic molecules. These newly developed
computational approaches, coupled with the astounding recent advances in computer power,
enable researchers to quantitatively explore problems in atomic, molecular, and optical physics
far beyond what was possible even a few years ago. This contribution to the symposium
dedicated Frank Harris will focus on how in the past few years, new and efficient algorithms have
been developed to solve the time-dependent Schrödinger equation (TDSE) and have revealed
some new and interesting physics. These approaches exploit a high level of computational
parallelism by treating the spatial discretization and time evolution aspects in a unified manner.
When coupled with the advances in and the availability of high-performance computing
platforms such as those of the NSF eXtremeDigital program, which is administered via the
eXtreme Science and Engineering Discovery Environment (XSEDE) project, and the Blue Waters
program, it is now possible to efficiently examine ultracold atoms subject to external fields and to
numerically generate nearly exact solutions for the interactions of short, intense laser pulses with
simple one- and two-electron systems.
14
O7
Recent progress in the variational approach to atomic and molecular
electronic structure
Carlos F. Bunge
Instituto de Fsica, Universidad Nacional Autonoma de Mexico,
Apdo. Postal 20-364, Mexico 01000, Mexico
Recent progress in selected conguration interaction (SCI) with truncation energy error [1] and CI
by parts [2] will be discussed together with applications. In atoms: (i) automatic optimization of
orbital bases to within a prescribed error, (ii) determination of positive-energy orbitals
incorporating electronic correlation coming from multi-reference CI singles and doubles which
also contain negative-energy orbitals, (iii) domain and accuracy of predictions of the Dirac-Breit
Hamiltonian; in molecules (i) pre-selection of huge numbers of congurations and sensitivity
analyses, and quantitative selection of tera plus congurations and corresponding truncation
energy error, (ii) improved selection methods, and (iii) critical code regions and latest
applications [3, 4].
[1] C.F. Bunge, J. Chem. Phys. 125,014107(2006).
[2] C.F. Bunge and R. Carbo-Dorca, J. Chem. Phys. 125,014108(2006).
[3] C.X. Almora-Daz, J. Chem. Phys. 140,184302(2014).
[4] C.X. Almora-Daz, H.I. Rivera-Arrieta, R.Hernandez-Aguilar and C.F. Bunge (unpublished).
15
O8
Selected configuration interaction with truncation energy error in
molecular systems: Symmetric dissociation of water
César X. Almora-Díaz and Carlos F. Bunge
Instituto de Física, Universidad Nacional Autónoma de México,
Apdo. Postal 20-364, México 01000, México
A priori selected configuration interaction (SCI) with truncation energy error (SCI-TEE) [1] and
CI by parts (CIBP)[2] for molecular systems has been implemented in our programs ATMOL and
AUTOCL for electronic structure of stationary states [3]. Altogether, SCI- TEE and CIBP allow
for: a) the construction of a model space that contains the principal configurations, and b) the
calculation of the energy truncation error from discarded configurations. In this way, we obtain
numerical approximations to Schrödinger’s equation with controlled and hence predictive
accuracy, which is one of the aims of electronic structure theory [4].
In order to test the method we carry out CI and FCI with double zeta basis sets for water at
equilibrium geometry and at geometries where the bond lengths are elongated up to dissociation
[5, 6]. In all cases we reproduce exact CI results (from CISD to FCI) to within 10 microhartree.
We also found that, as the system approaches dissociation, the number of selected configurations
decreases significantly.
[1] C.F. Bunge, J. Chem. Phys. 125, 014107 (2006).
[2] C.F. unge and R. Carb o-Dorca, J. Chem. Phys.125, 014108 (2006).
[3] C. . Almora- a , J. Chem. Phys. 140, 184302 (2014).
[4] T. Shiozaki, M. Kamiya, S. Hirata, and E.F. Valeev, J. Chem. Phys. 130, 054101 (2009).
[5] G.K-L. Chan, M Head-Gordon, J. Chem. Phys. 118, 8551 (2003).
[6] J. Olsen, P. Jorgensen, H. Koch, A. Balkova, R.J. Bartlett, J. Chem. Phys. 104, 8007 (1996).
16
O9
Viable and fleeting molecules containing He atoms
Herzain I. Rivera-Arrieta
Instituto de Fsica, Universidad Nacional Autonoma de Mexico,
Apdo. Postal 20-364, Mexico 01000, Mexico
Coupled-cluster calculations at the SD and SD(T) levels of approximation with augmented DZ,
TZ, QZ and 5Z have been used in a systematic exploration of viable and fleeting [1] molecules
containing one and two He atoms. Geometries and vibrational analyses of several positive as well
as negative He containing molecular ions, and even neutral species, will be reported together with
selected CI calculations with truncation energy errors [2] currently in progress.
[1] R. Homann, P. von Rague Schleyer, and H.F. Schaefer III, Angew. Chem. Int. Ed.
47,7164(2008).
[2] C.F. Bunge, J. Chem. Phys. 125,014107(2006).
17
O10
Multireference Fock space coupled cluster method for the
description of the dissociation of a single bond
Monika Musial
University of Silesia, Institute of Chemistry,
Szkolna 9, 40-006 Katowice, Poland [email protected]
The principal goal which underlines the current work is based on the so called DEA (double
electron attachment) strategy. The target of the correlated calculations for the standard neutral
molecule is placed on the calculations for the system in which the number of electrons is smaller
by two relative to the reference. This makes it possible to avoid well known problems occurring
in the situation when closed shell molecule dissociates into open shell fragments.
The newly implemented method [1] based on the multireference Fock space coupled cluster (FS-
CC) theory was used to determine potential energy curves and all relevant constants
characterizing chemical bond with experimental accuracy for systems which dissociate into
closed shell fragments after removing a pair of electrons.
[1] M. Musia l, J. Chem. Phys., 136, 134111 (2012)
18
O11
Application of the Active Space Self-Interaction-Correction Method
to Molecular Systems
F. Aparicio
Departamento de Ciencias Naturales, DCNI, UAM – Unidad Cuajimalpa, Av. Vasco de Quiroga 4871, Santa Fe, México D.F. México
Corresponding author: [email protected]
Within the context of the active space of the self-interaction-correction (SIC) optimized effective
potential (OEP) method [1, 2], the effect of the inclusion of the SIC at the level of only use the
HOMO orbital is analyzed for a set of small molecules and for a model of an interstitial region
surrounded by positively charged groups in a polypeptide; the model is representative of a class
of regions occurring in proteins. It is shown, for the molecular systems treated in this work, that
the inclusion of the HOMO orbital, within the SIC-OEP, induces a remarkable change on the
eigenvalue spectrum. For the interstitial state model, the improvement is systematic as one
increase the active space from one to ten orbitals; also, the influence on the local behavior of the
interstitial virtual state closest to the Fermi level is important and enhances its regional character.
As this method reduces the computational effort to introduce the SIC it seems promising to deal
with self-interaction-corrections in systems with many atoms/electrons such as biomolecules.
References
[1] Garza, J.; Vargas, R.; Nichols, J.A.; Dixon, D.A. J. Chem. Phys. (2001) 114, 639-651.
[2] Aparicio, F.; Garza, J.; Galván, M. J. Mex. Chem. Soc. (2012) 56, 338-345.
19
O12
Density Functional Methods for Extended Helical Systems
J. W. Mintmire
Department of Physics, Oklahoma State University, Stillwater, OK, USA
Corresponding author: [email protected]
Over the past several years we have made substantial progress in developing an approach for
density-functional electronic structure calculations on quasi-one-dimensional nanostructures with
helical symmetry. In this talk we discuss the application of these first-principles methods using
Gaussian basis sets for calculating the electronic band structure of periodic graphitic
nanostructures such as carbon nanotubes and graphene nanoribbons. In particular, we discuss the
numerical methods needed to evaluate gradients of the total energy. The gradients with respect to
changes in nuclear coordinates have similar algorithms for forces calculated in molecular DFT
codes, but the derivatives with respect to changes in lattice spacing and twist are more complex.
We present results for the application of these methods to graphitic strips and inorganic
nanowires.
This work was supported by the US DOE Grant DE-FG02-07ER46362.
20
O13
Photochromic behaviour of bicyclic boranates and TD-DFT
calculations
Rodrigo Morales-Cueto1, William Rodríguez-Córdoba
2, Victoria E González
1 Víctor Barba
1
1Centro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos, Av Universidad
1001 Col Chamilpa CP 62209 Cuernavaca, Morelos, México
2Escuela de Física, Universidad Nacional de Colombia Sede Medellín, Calle 59A No 63 - 20 Núcleo El
Volador, Medellín, Colombia
Corresponding author: [email protected]
Boronic acids are able to bind with diol units to form cyclic boronate esters. The interactions
inside the ring (5-7 members) allow a diol-based receptor system used to build sensors and
separation systems. Fluorescence is a remarkable property that maybe affected by the
environment. A series of byclic boronates were synthetized and chemical characterized in a
previous work[1]. Here we elucidate the effect of electroatractor (Methyl, Naphtil) and
electrodonor (Cl, NO2, COOH) in para position about the amino or hydroxil moiety within the
boronic ring and stability of principal conformers. Also, a photochromic effect when changing
the solvent polarity is appreciated as the color of the solution of -H subtituted compound changes.
We performed TD-DFT calculations with hybrid functionals B3LYP/631G**(Becke, 3-parameter,
Lee-Yang-Parr) and PBE0 (Perdew; Burke; Ernzerhof) using the Gaussian 09 suit program.
Preliminary results show similar results from boronic species on previous semiempirical (INDO)
calculations[4]. Photochromic behaviour was simulated using the Polarizable Continuum Model
(PCM) integrated into the Gaussian suite program.
References
[1] V. E. Gonzalez, F. Medrano, M. Rodriguez, P. G. Lacroix, V. Barba (2014) Tetrahedron
Letters Accepted.
[2] P.J. Stephens, F. J. Devlin, C. F. Chabalowski and M. J. Frisch (1994) J. Phys. Chem. 98 (45):
11623–11627.
[3] J.P. Perdew, K. Burke; M. Ernzerhof (1997) Physical Review Letters 77 (18): 3865–3868.
[4] H. Reyes, B.M. Muñoz, N. Farfán, R Santillán, S. Rojas-Lima, P.G Lacroix, K. Nakatani J.
Mater. Chem., (12), 2898–2903 . Figure 1. A temple
21
O14
Quantum Statistical Mechanics with Just One Orbital
S.B. Trickey
Dept. of Physics (QTP),
Univ. Florida
Both the size and complexity of systems to be studied by ab initio simulations grow inexorably.
The result is near prohibitive conflict between the relentless quest for chemical accuracy (defined
ever more stringently in much of quantum chemistry) and the need for fast simulations to screen
many systems and properties. Exploitation of computer speedups is a doomed strategy: not only
is there Amdahl's law, experience shows the extreme difficulty in using massively parallel
machines at truly massive levels. Method simplification with minimal loss of accuracy therefore
always is laudable.
Ab initio molecular dynamics (AIMD) is computationally tractable today mostly because of
density functional theory (DFT), in particular, effective exchange-correlation (XC)
approximations. Most recent effort at bettering the XC functionals has been focused on the
chemical accuracy issue. Thus, "third- and fourth-rung" XC fuctionals depend explicitly on
Kohn-Sham (KS) orbitals. Those worsen the computational scaling of AIMD from being
proportional to N3 (N = number of electrons) to N
4 or worse. That matters little for simple
systems and only a few simulations. It matters a lot for large-scale AIMD-DFT studies over a
wide range of physical or chemical conditions. Each run may have tens-of-thousands MD steps,
with N=100 to 1,000. Many runs are required. Observe that the same problem arises in
geometry optimization of extremely large, complicated clusters.
For high-through-put, even N3 scaling is not good. Thus in 2004 or so, Frank Harris and I
independently became interested in orbital-free DFT. We then partnered with Valentin Karasiev
to begin a project that subsequently has branched into finite-temperature DFT at rather high
(multi-electron volt) temperatures (with Jim Dufty, Keith Runge, Travis Sjostrom, Tamas Gal,
and Deb Chakraborty). We have focused upon so-called "lower-rung" kinetic energy and entropy
functionals. Such functionals depend upon the density and density gradient at most. Another
collaboration, with colleagues in México, has continued to focus on lower-rung XC functionals.
All (KE, entropy, XC) are constraint-based, i.e. non-empirical. I will sketch the structure of this
somewhat unfamiliar form of DFT, note its main difficulties, report our recent progress on
functionals and give a few examples of their use.
Supported in part by U.S. D.O.E. grant DE-SC0002139.
22
O15
Robust and efficient evaluation of hartree-fock exchange
Andreas M. Köster, Daniel Mejía-Rodríguez
Departamento de Química, Centro de Investigación y de Estudios Avanzados
Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, D.F., C.P. 07360, MÉXICO
The calculation of Hartree-Fock exchange is computationally cumbersome. In this work we
present a new local density fitting approach that permits the efficient calculation of Hartree-Fock
exchange with three-center electron integrals only. Our approach exploits the short range nature
of Hartree-Fock exchange by using localized molecular orbitals. It also takes advantage of the
spherical averaging of the exchange hole as utilized in density functional theory. The
implementation of this new density fitting Hartree-Fock exchange into deMon2k [1] is presented.
Benchmark calculations show its superior computational performance with respect to
conventional four-center integral approaches. The construction of hybrid functionals in the
framework of auxiliary density functional theory [2] is discussed.
Keywords: Hartree-Fock Exchange, Density Fitting, deMon2k
References: [1] See www.demon-software.com
[2] V.D. Dominguez-Soria, P. Calaminici, A.M. Köster, Variational Fitting in Auxiliary Density
Functional Theory, in Theoretical and Computational Developments in Modern Density
Functional Theory, Editor: A.K. Roy, Nova Science Publisher, NY, USA (2012)
Presenting author’s email: akoster@cinvestav
23
O16
The dynamic interaction of the PtSn bimetalic cluster with ethanol
I.P. Zaragoza
Instituto Tecnológico de Tlalnepantla, División de Posgrado
e Investigación, Av Mario Colín S/N La Comunidad, Tlalnepantla de Baz
C.P. 54070, Estado de México, México
R. Santamaria
Instituto de Física, Universidad Nacional Autónoma de México,
Circuito Exterior S/N Coyoacan, D.F. C.P. 01000, México
The dynamic interaction of the bimetallic cluster PtSn with ethanol (CH3 − CH2 − OH)
is investigated. The interaction is sufficiently reactive that different types of bond breaking
occur. We find the breaking of either the OH fragment or the CH moity of ethanol. The
final products of the reaction depend of the initial conditions of the molecular dynamics. The
charge transfer and energy changes are determined and discussed in terms of the interaction
distance between compounds. The reaction dynamics is important to understand both the
catalysis of ethanol by specialized metals and the building of fuel cells based on ethanol.
Density functional theory in combination with classical molecular dynamics is used in the
investigation of the chemical reactions.
Keywords: reaction mechanism, bimetallic cluster, ethanol, density functional theory,
molecular dynamics
PACS: 31.15.E, 68.43.Bc, 82.75.Qt, 31.15.xv, 71.15.Pd
Corresponding author: [email protected]
24
O17
Wave-Packet Dynamics and Group Theory
Yngve Öhrn
Quantum Theory Project, University of Florida, Gainesville, FL, USA
The mathematics and connection to symmetry of Gaussian wave-packet dynamics with evolving
width is discussed in terms of the time-dependent variational principle.
O18
Fidelity in Multiscale Modeling: A Frank Assessment
Keith Runge1, Krishna Muralidharan
2, and Pierre A. Deymier
2
Department of Physics, University of Florida, Gainesville, FL, USA
Engineering, College of Materials Science and Engineering, University of Arizona, AR, USA
Many phenomena that impact on the performance of materials and processes are driven by their
behavior at the atomistic scale. Insights from quantum chemistry are essential for the description
of physical processes at the atomistic scale. A frequently used tool for examining the behavior of
materials systems is molecular dynamics simulations, however, the computational requirements
for ab initio or direct dynamics where forces are calculated on-the-fly from quantum chemical
theory can be quite daunting. This is particularly true in cases where chemical bonds are breaking
and/or forming and hence a method for using quantum chemical methods in smaller regions of
space inside atomistic descriptions at larger scales. A framework for achieving such a multiscale
model is called consistent embedding, which will be exemplified by a number of examples
including fracture of amorphous silica and fragmentation of buckyballs.
25
O19
Multi-resolution approach for laser modified collisions of atoms and
ions
F. Javier Domínguez-Gutiérrez1,2, R. Cabrera-Trujillo
1, and Predrag S. Krstic
2
1Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México,
Ap. Postal 43-8, Cuernavaca, Morelos, 62251, México
2Institute for Advanced Computational Science, Stony Brook University,
Stony Brook, NY 11749-5250, USA
Corresponding author: [email protected]
Multiresolution Adaptive Numerical Environment for Scientific Simulation (MADNESS) uses
highly accurate multiresolution analysis, separated representation and adaptive numerical mesh to
solve the Schrödinger equation in an arbitrary number of dimensions [1]. It’s functionality was
expanded to solve the time-dependent Schrodinger equation (TDSE) and treat atomic transition
dynamics in a time-dependent laser field [2]. We here expand the functionality of the
MADNESS-TDSE time evolution band-limited, gradient-corrected, symplectic propagator
approach to describe collision dynamics of single-electron ions and atoms in a strong femto-
second laser field to unsurpassed accuracy. We apply this method to H⁺ + H(2s) collision system
modified by presence of the 800 nm laser field of terawatt intensity in a wide range of collision
energies (100 eV to 25 keV). We calculate the charge transfer, excitation and ionization
processes, validating our results with existing experimental and theoretical data reported in
literature.
References
[1] R. Harrison et. al., J. Chem. Phys. (2004) 121, 2866.
[2] N. Vence at al, Phys. Rev. A (2012) 85, 033403.
26
O20
Inspired by Frank Harris: Recent Developments with the Electron
Nuclear Dynamics and Coupled Cluster Theories
Ajith Perera1, Jorge A. Morales 2
1Department of Chemistry, Quantum Theory Project, University of Florida, Gainesville, FL 32611
2Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
Corresponding author: [email protected]
In this lecture, we would like to celebrate Prof. Frank Harris’ scientific life by presenting some of
our recent developments with the electron nuclear dynamics (END) [1] and coupled cluster (CC)
theories [2]. END is a time-dependent, variational, non-adiabatic and direct method to simulate
chemical reactions. The simplest-level END (SLEND) describes nuclei classically and electrons
with a single-determinantal wavefunction. Within SLEND, we will present three interrelated
novel developments1: (1) the formulation of different types of coherent states to generate
quantum/classical connections for various degrees of freedom: rotational, vibrational (both
harmonic and anharmonic), and electronic. (2) The new SLEND Kohn-Sham density functional
theory method. And (3) our cutting-edge parallel code PACE (Python Accelerated Coherent-states
Electron nuclear dynamics) implementing the aforesaid models. These models successfully
simulate various chemical reactions, including high-energy ion-molecule collisions, and SN2 and
Diels-Alder reactions. However, the more prominent applications of our models are to proton
cancer therapy reactions, such as water radiolysis and damage processes in DNA components.
For the CC theory, we will present our ongoing development of novel CC methods in a massively
parallel manner to compute various types of properties in large molecules [2]. Properties include
all the quantities in the electron spin resonance (ESR) spectrum (i.e. isotropic hyperfine coupling
constants, g- and D-tensors) and static polarizabilities. This project is conducted with the aid of a
new domain-specific software paradigm developed by the Bartlett research group for their
massively parallel code ACES III [3]. At present, capabilities to calculate isotropic hyperfine
coupling constants [2] and static polarizabilities have been implemented and applied to various
organic radicals and molecules, respectively. Notably, the predicted isotropic hyperfine coupling
constants are for radicals of up to 35 atoms and with up to 925 basis functions [2]: These are
among the largest applications of the CC theory in general and the largest CC prediction of ESR
spectra to date. In addition, we will present our ongoing development of CC capabilities to
calculate the ESR g- and D-tensors and their applications to large radicals.
References
27
[1] C. Stopera, T. V. Grimes, P. M. McLaurin, A. Privett, J. A. Morales, Adv. Quant. Chem.
(2013), 66, 3, 113-194.
[2] P. Verma, S. A. Perera, and J. A. Morales, J. Chem. Phys. (2013) 139, 174103.
[3] V. Lotrich, N. Flocke, M. Ponton, A. D. Yau, A. Perera, E. Deumens, R. J. Bartlett, J. Chem.
Phys. (2008) 128, 194104.
O21
Conformational Electroresistance and Hysteresis in Nanoclusters
Hai-Ping Cheng, Xiang-Guo Li, and X.-G. Zhang
Department of Physics and Quantum Theory Project, University of Florida,
Gainesville, Florida 32611, United States
The existence of multiple thermodynamically stable isomer states is one of the most fundamental
properties of small clusters. This work shows that the conformational dependence of the
Coulomb charging energy of a nanocluster leads to a giant electroresistance, where charging
induced conformational distortion changes the blockade voltage. The intricate interplay between
charging and conformation change is demonstrated in a nanocluster Zn3O4 by combining a first-
principles calculation with a temperature-dependent transport model. The predicted hysteretic
Coulomb blockade staircase in the current-voltage curve adds another dimension to the rich
phenomena of tunneling electroresistance. The new mechanism provides a better controlled and
repeatable platform to study conformational electroresistance.
[1] Xiang-Guo Li, X.-G. Zhang, and Hai-Ping Cheng , Nano Lett., 2014, 14 (8), 4476 (2014)
28
O22
Transition State Search of Finite Systems
Patrizia Calaminici
Departamento de Química, Centro de Investigación y de Estudios Avanzados,
Av. Inst. Politécnico Nacional 2508, Col. San Pedro Zacatenco, D.F.,
C.P. 07360, MÉXICO
Email: [email protected]
The results of a transition state search of different finite systems such as selected metal clusters
and biological systems will be presented. These systems are particularly interesting due to the
fact that in mostly of the cases their transition states are not intuitive. For this purpose a
hierarchical transition state search algorithm [1] as it is implemented in the deMon2k code [2] has
been employed. This algorithm combines the double ended interpolation method with local uphill
trust region optimization. The main features of this algorithm as well as the performance of its
validation will be reviewed. Finally, applications to selected finite systems like sodium clusters
[3], aluminum clusters [4] and glycerol conformers [5] will be discussed.
References:
[1] J.M. Del Campo, A.M. Köster, J. Chem. Phys. 129 (2008) 024107.
[2] See http://www.demon-software.com
[3] D. Cruz Olvera, A de la Trinidad, J.M. Vásquez-Pérez, P. Calaminici, A.M. Köster, submitted
to J. Phys. Chem. (2014)
[4] A. Prado, J.M. Vásquez-Pérez, P. Calaminici, A.M. Köster, to be submitted
[5] A. Goursot, T. Mineva, J.M. Vásquez-Pérez, P. Calaminici, A.M. Köster, D.R. Salahub, Phys.
Chem. Chem. Phys. 15 (2013) 860.
29
O23
Excited states of Nonlinear Schrödinger Equation and nonlinear
coupling impurity in a matter waveguide: analytical solutions and
their properties
Ricardo Mendez Fragoso1 and Remigio Cabrera-Trujillo
2
1Facultad de Ciencias, UNAM
2Instituto de Ciencias Físicas, UNAM
The dynamics of Bose-Einstein condensates in atomic chips and waveguides is studied by means
of the Gross-Pitaevskii equation (GPE). This is the nonlinear Schrödinger (NLS) equation and
describes an ensemble of atoms occupying the same state. In the present contribution the structure
of quantum states is studied on the threshold of de-localization, i.e., when the energy spectra goes
from the discrete to continuum. We use analytical solutions and numerical simulations for the
one-dimensional GPE as a model of waveguide for ultracold matter. The defects of that
waveguide have been effectively modeled by a square potential for different widths R0 and depths
V0. One feature of the NLS is the nonlinear term proportional to the cube of the wave function
and it has an intensity parameter, g, which models the interactions of the particles in the condensate. This work shows special emphasis on excited states that can be found in coexistence
with the ground state, however the description of the system can not be done using the
superposition principle due to the nonlinearity. We report the first excited state exists only when R0√V 0⩾π/2√2
. We discuss the implications of these results in the propagation processes of
ultra-cold matter in waveguide. Analytical results presented allow us to calculate properties that
can be measured experimentally as a function of the condensate size in terms of the geometric
parameters of the trap.
We acknowledge the support from DGAPA-UNAM grants PAPIIT IN-IA-102-414 and IN-110-
714.
30
O24
Second-order nonlinear optical susceptibilities and refractive indices
of organic crystals from a multi‐ scale numerical simulation
approach
Benoít Champagne
Laboratory of Theoretical Chemistry,
University of Namur, Namur, Belgium [email protected]
In this contribution it is shown that a multi-scale approach combining first principles evaluations
of the molecular properties with electrostatic interaction schemes to account for crystal
environment is reliable for predicting and interpreting the experimentally-measured electric linear
and second-order nonlinear optical susceptibilities. This is illustrated by considering organic
crystals including ionic crystalline salts. A good agreement between theory and experiment is
achieved providing the electric field effects originating from the electric dipoles of the
surrounding molecules are accounted for. The presentation will also i) highlight the key role of
the geometry on the χ(1) and χ(2) responses, ii) demonstrate the impact of electron correlation on
the molecular and crystal properties, iii) assess the performance of exchange-correlation
functionals, and iv) address the amplitude of the zero‐ point vibrational energy contributions [1-
2].
[1] Seidler, T., Stadnicka, K., Champagne B., J. Chem. Phys., 139,114105 (2013).
[2] Seidler, T., Stadnicka, K., Champagne B., J. Chem. Theor. Comput. 10, 2114 (2014).
31
O25
Density Cumulant Functional Theory
Henry Schaefer
Department of Chemistry
University of Georgia
Athens, GA, 30602, USA
O26
Quantum Effects in Many-Body Systems Described By Classical
Methods
James W. Dufty and Jeffrey Wrighton
Department of Physics, University of Florida, Gainesville, FL, USA
Sandipan Dutta
Asia-Pacific Center for Theoretical Physics, Pohang 790-784, South Korea
A recent description of an exact map for the equilibrium structure and thermodynamics of a
quantum system onto a corresponding classical system is summarized. Applications to the
uniform electron gas and harmonically confined charges are described for a wide range of
temperatures and densities. Where available, comparisons are made to recent path integral Monte
Carlo simulations (PIMC) with good agreement. The relationship to orbital free density
functional theory for conditions of warm, dense matter are discussed.
[1] J. W. Dufty and S. Dutta, Contrib. Plasma Phys. 52 100 (2012); Phys. Rev. E 87 032101
(2013).
[2] S.Dutta and J. Dufty, Phys. Rev. E 87, 032102 (2013); S. Dutta and J. Dufty, Euro. Phys.
Lett., 102 67005 (2013).
32
O27
A photoelectron spectrometer for measuring angular distributions in
photoionization and photodetachment of positive and negative
ions using synchrotron radiation
O. Windelius1, D. Hanstorp
2, J. Rohlén
2, A. Juarez
3, I. Rebolledo-Salgado
3, J. de Urquijo
3, J.J.
Valerio-Torres3, B. Bates
4, R.Bilodeau
4, T. Castel
4, A. Aguilar
4
1Department of Physics, University of Gothenburg and Department of Applied Physics, Chalmers
University of Technology, S-41296 Göteborg, Sweden ([email protected])
2Department of Physics, University of Gothenburg, S-41296 Göteborg, Sweden
3Institute of Physical Sciences, National University of Mexico, 62210 Cuernavaca Morelos, Mexico
4Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
The total cross sections of photoionization processes have been measured using merged beams at
various synchrotron facilities by our group in the past (e.g. ALS [1], MAX-LAB [2]). However,
less information exist about the differential cross sections from the photoionization of positive
and negative ions. Except a few instances, angular distribution of photoelectros emmited from
photoionization of ions has not yet been possible using synchrotron radiation. The aim of this
project is therefore to develop a photoelectron spectrometer for merged beams in a synchrotron,
that will work despite the low intensity of the photon beam. The design is based on a concept
tested using laser sources [3]. The spectrometer is currently commissioned at the ion beam
facility GUNILLA in Gothenburg [4] and thereafter installed at beamline 10.0.1 of the
synchrotron facility at ALS, Berkeley.
Figure 1.
a) The graphite tube with holes. The filter and lens are cut from one side for visual reasons.
b) Tube and detectors, the actual setup contains detector chambers in all four directions.
The spectrometer consists of a graphite tube with holes in four directions surrounded by filters
through which electrons of energies above a certain level are allowed to escape into chambers
33
containing detectors. In each direction, an electrostatic lens placed after the filter steers the
electrons into the detector. (see Fig. 1)
Receent measurements on angular distributions of photodetached C- ions will be presented in the
workshop. The first experiment with the device when installed at the ALS will be photoionization
of Cr+
[5].
References
[1] Covington A.M., Aguilar A., Covington I.R., et al., "Photoioinization of Ne+ using
synchrotron radiation", Phys. Rev. A, 66, 062710 (2002).
[2] https://www.maxlab.lu.se
[3] Hanstorp D., Bengtsson C., Larson D.J., "Angular distributions in photodetachment from O-,"
Phys. Rev. A, 40, 670 (1989)
[4]http://www.physics.gu.se/forskning/atomic_and_molecular/experimentellatomfysik/utrustning/
[5] Dolmatov, V.K., Guler E. and Manson S.T., "Reading the photoelectron -parameter
spectrum in a resonance region," Phys. Rev. A 76, 032704 (2007)
This work was supported by DOE, The Swedish Research Council and CONACYT through grant
CB-2011 167631
34
O28
Electron transport calculated from first-principles complex bands
X.-G. Zhang1,2, Y. Wu1, K. Varga3, S. T. Pantelides3,4
1Department of Physics, University of Florida, Gainesville, FL 32611
2Center for Nanophase Materials Sciences and Computer Science and Mathematics Division, Oak Ridge
National Laborator, Oak Ridge, TN 37831
3Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235
2Material Sciences and Technology Division, Oak Ridge National Laborator, Oak Ridge, TN 37831
Corresponding author: [email protected]
Using a generalized Bloch theorem for complex periodic potentials and a transfer-matrix
formulation we cast the transmission probability in a scattering problem with open boundary
conditions in terms of the complex wave vectors of a periodic system with absorbing layers,
allowing a band technique to yield quantum transport properties. Application to the resistance of
a twin boundary in nanocrystalline copper [1] yields excellent agreement with recent
experimental data [2]. This method is further developed for the calculation of carrier mobility in
silicon due to impurity and phonon scattering. The calculation is entirely from first-principles
without any adjustable parameters. The results for both impurity and phonon cases are in good
agreement with experiment.
References
[1] X.-G. Zhang, K. Varga, S. T. Pantelides, Phys. Rev. B (2007) 76, 035108.
[2] L. Lu, Y. Shen, X. Chen, L. Qian, K. Lu, Science (2004) 304, 422.
35
O29
Different oxidation states in CrF2 determined by comparison of a
ligand field multiplet calculation and absorption and resonant x-ray
emission at the chromium L2,3 edge
José Jiménez-Mier,a Paul Olalde-Velasco,
a,b,c Wanli Yang,
b Jonathan Denlinger.
b
aInstituto de Ciencias Nucleares, UNAM.
bThe Advanced Light Source, Lawrence Berkeley National Laboratory.
cSwiss Light Source, Paul Scherrer Institut, Switzerland.
Very good agreement was found between the x-ray absorption spectrum of CrF2 at the chromium
L2,3 edge and a crystal field multiplet calculation. To achieve such an agreement it was necessary
to include three chromium oxidation states, namely Cr+, Cr2+ and Cr3+. The same theoretical
parameters were used to calculate the resonant x-ray emission spectra (RIXS). For each spectrum
a superposition of the three oxidation states was compared with the experiment, where the
superposition coefficients were obtained by a least squares fitting of the experimental data.
Excellent agreement between experiment and theory was achieved. This comparison allowed a
partition of the CrF2 RIXS map into the three chromium oxidation states.
36
O30
The hydrogen molecular ion confined in dihedral angles
S. A. Cruz1, E. Ley-Koo
2
1Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa Apartado Postal 55 534, 09340, México, D.F., México.
2Instituto de Física, Universidad Nacional Autónoma de México,Apartado postal 20 364 01000, México, D.F., México.
Corresponding author: S.A. Cruz, [email protected]
The study of the electronic structure of the hydrogen molecular ion confined in dihedral angles
was anticipated in Ref. [1]. The hamiltonian for the physical system is the same as that of the free
molecular ion. The confinement in the dihedral angle is modeled by the boundary conditions of
the vanishing of the electronic wavefunction at the positions of the meridian half-planes defining
the angle. The rotational symmetry around the nuclear axis, within the Born-Oppenheimer
approximation, is broken by the confinement: the eigenvalues of the z-component of the angular momentum are no longer integer. The exact eigenfunctions to be reported are restricted to the
lower eigenstates, using the same methodology developed in [2], taking into account the above-
mentioned symmetry breaking.
References
[1] E. Ley-Koo, G-H. Sun, Surface Effects in the Hydrogen Atom Confined by Dihedral Angles.
Chapter 1 in Electronic Structure of Quantum Confined Atoms and Molecules , Ed. Kalidas Sen,
Springer International Publishing, Switzerland (2014) .
[2] E. Ley-Koo, S. A. Cruz, The Hydrogen Atom and the H2+ and HeH
++ Molecular Ions Inside
Prolate Spheroidal Boxes, J. Chem. Phys. (1981), 74, 4603.
37
O31
Rules and Experiments for (Super)Conducting Polymers
Hendrik J. Monkhorst
Quantum Theory Project
University of Florida, Gainesville FL 32611-8435
Fifty years ago, Bill Little [1] made an intriguing proposal guiding the search for high-
temperature super-conducting polymers. He imagined an excitonic mechanism that provides an
effective electron pair coupling. According to this mechanism, highly polarizable side groups to
the polymer backbone may give an attractive force on each electron with a component parallel to
the backbone axis that may offset the repulsive force between them, at least for large separations
over several unit cell distances. Because the envisioned electron pairing would be mediated by
interactions with other electrons, rather than phonons, he argued that superconductivity would
occur at high temperatures, possible above room temperature.
Little and others made many attempts to synthesize appropriate polymer systems, but none were
superconducting, or even good conductors. In our opinion, at least four conditions for polymer
superconductivity were not satisfied: the polymer should 1) have intrinsic conductivity, with a
nonzero density-of-states at its Fermi level; 2) have highly polarizable side groups, containing
atoms like sulphur or iodine; 3) be highly ordered, preferably in crystalline form, or at least
ordered as thin films, and 4) have an intrinsic resistance to Peierls distortion, or due to 2D or 3D
interactions in film or crystalline environments, respectively.
I will explain the reasons for these conditions [2], point out experimental supports, and current
synthetic efforts [3].
References
[1] Little, W.A., Possibility of Synthesizing an Organic Superconductor, Phys. Rev. 134, 1414
(1964)
[2] Aissing, A. Monkhorst, H.J., Rules for Intrinsically (Super) Conducting Polymers, Int. J.
Quantum Chem. 27, 245-248 (1993)
[3] Chen, M.S. et al, Synthetic control of solid-state order and polymer-packing orientation for
enhanced organic electronic device performance, Abstract 538, 248th ACS Meeting, August 10-
14, 2014, San Francisco, CA
38
O32
Calculation of shell corrections to stopping power from dipole
oscillator sum rules
Jens Oddershede1,2, John F. Ogilvie1,3, John R. Sabin1,2
1Department of Chemistry, Physics, and Pharmacy, University of Southern Denmark, 5230 Odense M,
Denmark
2Departments of Physics and Chemistry, University of Florida, Gainesville, FL 32611, USA
3 Escuela de Quimica y Centro de Investigacion en Electroquimica y Energia
Quimica,Universidad de Costa Rica,Ciudad Universitaria Rodrigo Facio,San Pedro de Montes
de Oca, San Jose 11501-2060 Costa Rica
Corresponding author: [email protected]
The stopping power of a substance refers to the energy lost by a fast projectile to a target as it
traverses the target. The process was described by Bethe [1], and found to depend mainly on the
target oscillator strength distribution. For projectiles with velocities higher than those of the target
electrons, the mean excitation energy, or first energy weighted moment of the dipole oscillator
strength distribution, referred to as the mean excitation energy, , given by
ln I 0=∫
df
dEln E dE
∫df
dEdE
describes the energy transfer. For projectiles moving with velocities similar to those of the target
electrons, this approximation is not sufficient, and the full Bethe form must be used. Shell
corrections are the difference between the full Bethe stopping power and its dipole approximation
in terms of the Bethe logarithm. Knowledge of the projectile velocity dependent computed shell
corrections is needed for experimental determination of mean excitation energies. Previous
methods for calculating shell corrections are not fully consistent with the Bethe theory. We report
a new method for the calculation of shell corrections from dipole oscillator strength sum rules
that expresses the difference between the Bethe logarithmic term and the exact Bethe expression
for stopping in terms of dipole oscillator strength sum rules.
Test results for Hydrogen are compared with other ways of calculating shell corrections.
References
[1]. H. Bethe, Ann. Phys. 397, 325 (1930)
0I
39
O33
Excitons and Polarons in Oligosilane Chains: Five Stereoactive
Hybrid Orbitals and Valence Shell Expansion on a Silicon Atom
Matthew K. MacLeod1, Mari-Carmen Piqueras
2,3, Raul Crespo
2,3, and Josef Michl
1,3
1Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309-0215,
USA
2Department of Physical Chemistry, University of Valencia, Spain
3Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic,
16610 Prague, Czech Republic
Spectroscopy has shown that in peralkylated linear silicon chains SinR2n+2 with ~30 > n >
7, electronic excitation to the first excited singlet state S1 is delocalized over the chain length,
when n < 7, it is localized, and when n = 7, either situation obtains depending on chain
conformation. These results are reproduced by TDDFT calculations and can be rationalized in
simple terms. Presently, we deal with the nature of the large geometrical distortions that occur
during the relaxation of the S1 state and lead to hugely Stokes-shifted fluorescence, blue or green,
depending on conformation. From a combination of computational methods, we find that there
are two types of such distortion, one leading to the observed blue and the other to the observed
green emission. In the former case, two adjacent Si atoms are distorted from tetrahedral half way
to trigonal bipyramidal geometry, and in the latter case, one Si atom is trigonal bipyramidal. In
both cases, the distorted Si atoms are found to be using five hybrid orbitals to accommodate their
valence electrons. The fifth orbital originates in 4s and 4p AOs with a small admixture of 3d
AOs, and is intermediate in size between valence and Rydberg orbitals. Calculations on positive
and negative polarons (radical ions) in the case n = 4 show that charge and spin can also be
delocalized or localized and that a large number of conformers of comparable energies exist (for
the radical anion, 30 distinct minima in the ground state surface). In the localized form, one Si
atom is again trigonal bipyramidal, with four vertices occupied by methyl and silyl groups and
the fifth carrying a radical center. These results reopen the old issue of valence shell expansion in
atoms of main group elements.
40
O34
Dr. Harris or: How we learned to stop worrying and love the Bessel
function
Victor V. Albert
Departments of Applied Physics and Physics, Yale University, New Haven, Connecticut 06520, USA
About 15 years ago, my (future) undergraduate mentor Prof. Harris noticed that spherical Bessel
expansions of certain integrals were not developed. He thus went on to develop said expansions
by himself [1], earning a citation on the popular Wolfram MathWorld website [2]. I will discuss
his work and mention an episode from my current research [3] in which I have encountered
strikingly similar Bessel function sums and integrals. I will conclude with a frank summary of the
impact Prof. Harris has had on my personal and professional well-being.
[1] Harris, F. E. "Spherical Bessel Expansions of Sine, Cosine, and Exponential Integrals." Appl.
Numer. Math. 34, 95 (2000).
[2] Weisstein, E. W. "Exponential Integral." From MathWorld--A Wolfram Web Resource.
http://mathworld.wolfram.com/ExponentialIntegral.html.
[3] Mirrahimi, M. et al., “ ynamically protected cat-qubits: a new paradigm for universal
quantum computation.” New J. Phys. 16, 045014 (2014).
41
O35
Statistical Inference with Minimum Relative Entropy: A robust
numerical algorithm employing sinc quadrature
V.G. (“ ill”) Koures,
IISAM L3C
1712 Pioneer Ave.
Cheyenne, WY 82001
Bill Koures <[email protected]>
Given partial information (i.e., constraints) about a probability distribution, the distribution that
maximizes the entropy with respect to the constraints is the one that is least prejudiced about the
missing information. As new information arrives, the prior distribution must change. To maintain
maximum uncertainty given new information, we must minimize the relative entropy (the
Kullback Leibler distance) between the prior (p0) and posterior (p) distributions. Robust
constrained optimization algorithms to implement this minimization have proven difficult to find.
However, such an algorithm, that incorporates sinc quadrature and is applied to option market
fitting, is presented here. The quick convergence and robust behavior of this algorithm may open
up statistical inference with MRE to a wider range of scientific applications.
42
Registered participants
Victor V. Albert
Departments of Applied Physics and Physics,
Yale University, New Haven, Connecticut
06520, USA
César X. Almora-Díaz
Instituto de Fisica, UNAM
Rod Bartlett
Quantum Theory Project
University of Florida
Gainesville, Florida 32611-8435, USA
Carlos F. Bunge
Instituto de Fisica, UNAM
Remigio Cabrera-Trujillo
Instituto de Ciencias Física
UNAM, Cuernavaca, Morelos
Patrizia Calaminici
Depto. de Quimica,
Cinvestav, Mexico-City
Benoît Champagne
University of Namur
rue de Bruxelles, 61 B-5000 Namur
Ryan Chancey
Nelson Forensics,
2740 Dallas Pkwy Ste 220 Plano, TX 75093
Hai-Ping Cheng
University of Florida
Gainesville, Florida 32611-8435, USA
Salvador A. Cruz Jimenez
Departamento de Física, UAM-I
Apartado Postal 55 534, 09340 México, D.F.
Fco. Javier Domínguez-Gutiérrez
Instituto de Ciencias Físicas, UNAM
Av. Universidad s/n, Col. Chamilpa, Cuernavaca,
Morelos, 62210, México.
James W. Dufty
University of Florida
Gainesville, Florida 32611-8435, USA
Joseph G. Fripiat
Laboratoire de Chimie Théorique, Dpt Chemistry,
University of Namur, rue de Bruxelles, 61 B-5000
Namur, Belgium
Frank E. Harris
Quantum Theory Project
University of Florida
Gainesville, Fl orida 32611-8435, USA
José Jiménez-Mier
Instituto de Ciencias Nucleares, UNAM
Ciudad Universitaria, México, D.F.
Antonio Juárez
Instituto Ciencias Físicas
UNAM, Cuernavaca, Morelos
Per Kaijser
KRI, Moarstrasse 18, 85737 Ismaning, Germany
Andreas M. Köster
Depto. de Quimica, CINVESTAV, Mexico-City
V.G. (“ ill”) Koures,
Heritage Hall
1800 NW 122nd St.
Oklahoma City, OK 73120
Bill Koures <[email protected]>
43
Eugenio Ley-Koo
Instituto de Física, UNAM
Ciudad Universitaria, México D.F.
Ricardo Méndez-Fragoso
Facultad de Ciencias, UNAM
Circuito Exterior, Ciudad Universitaria, México
04510, D.F.
Josef Michl
Department of Chemistry and Biochemistry,
University of Colorado,
Boulder, CO 80309-0215, USA
John W. Mintmire
Department of Physics, PS 145
Oklahoma State University
Hendrik J. Monkhorst
Quantum Theory Project,
Department of Physics, University of Florida,
Gainesville FL 342611-8435
Jorge A. Morales
Texas Tech University
P.O. Box 41061 Lubbock, TX 79409-1061
Rodrigo Morales-Cueto
CIQ-UAEM
Av UNiversidad 1001
Monika Musial
University of Silesia
Szkolna 9, Poland
Jens Oddershede
Department of Physics, Chemistry and Pharmacy,
University of Southern Denmark,
Campusvej 55, DK-5230 Odense M, Denmark
Yngve Öhrn
QTP, University of Florida
Gainesville, Florida 32611-8435, USA
Ajith Perera
QTP, University of Florida
Gainesville, FL, 32611
José Récamier Angelini
Instituto de Ciencias Física, UNAM,
Herzain Rivera-Arrieta
Instituto de Fisica, UNAM
Keith Runge
QTP, University of Florida
Gainesville, Florida 32611-8435, USA
John R. Sabin
QTP, University of Florida
Gainesville, Florida 32611-8435, USA
Henry Schaefer
Department of Chemistry
University of Georgia
Athens, GA, 30602, USA
Barry Schneider
Applied and Computational Mathematics Division,
Information Technology Laboratory
National Institute of Standards and Technology
100 Bureau Drive, M/S 8910
Gaithersburg, MD 20899-8910
Frank Stenger
University of Utah
Salt Lake City, UT 84112
Sam B. Trickey
QTP, University of Florida
Gainesville, Florida 32611-8435, USA
Alberto Vela Amieva
Departamento de Química
CINVESTAV, IPN
44
Irineo Pedro Zaragoza,
Instituto Tecnológico de Tlalnepantla,
Av. Mario Colin S/N Tlalnepantla de Baz
Alphabetical Index
Aguilar, A. ........................................................ 32
Albert, Victor V. ......................................... 40, 42
Almora-Díaz, César X. ................................ 15, 42
Aparicio, F. ....................................................... 18
Barba, V. .......................................................... 20
Bartlett, Rod .................................................... 42
Bates, B............................................................ 32
Bilodeau, R. ..................................................... 32
Bunge, Carlos F. ................................... 14, 15, 42
Cabrera-Trujillo, R. ............................... 25, 29, 42
Calaminici, Patrizia .................................... 28, 42
Castel, T. .......................................................... 32
Champagne, Benoit ................................... 30, 42
Chancey, Ryan ................................................. 42
Cheng, Hai-Ping ......................................... 27, 42
Crespo, Raul .................................................... 39
Cruz, S. A. .................................................. 36, 42
de Urquijo, J. ................................................... 32
Denlinger, Jonathan ......................................... 35
Deymier, Pierre A............................................. 24
Domínguez-Gutiérrez, F. Javier .................. 25, 42
Dufty, James W. ......................................... 31, 42
Fripiat, Joseph G. ....................................... 10, 42
González, V. E. ................................................. 20
González-Gutiérrez, C. ..................................... 11
Hanstorp, D. .................................................... 32
Harris, Frank E. ................................................ 42
Jiménez-Mier, José .................................... 35, 42
Juarez, A. ................................................... 32, 42
Kaijser, Per ................................................. 12, 42
Köster, Andreas M. .................................... 22, 42
Koures, V.G. ( ............................................. 41, 42
Krstic, Predrag S. .............................................. 25
Ley-Koo, E. ............................................. 9, 36, 43
Li, Xiang-Guo ................................................... 27
MacLeod, Matthew K. ..................................... 39
Mejía-Rodríguez, Daniel .................................. 22
Méndez-Fragoso, R. ............................... 9, 29, 43
Michl, Josef ................................................ 39, 43
Mintmire, J. W. ........................................... 19, 43
Monkhorst, Hendrik J. ................................ 37, 43
Morales, Jorge A. ....................................... 26, 43
Morales-Cueto, R. ...................................... 20, 43
Muralidharan, Krishna...................................... 24
Musial, Monika .......................................... 17, 43
Oddershede, Jens ....................................... 38, 43
Ogilvie, John F. ................................................. 38
Öhrn, Yngve................................................ 24, 43
Olalde-Velasco, Paul ......................................... 35
Pantelide, S. T. .................................................. 34
Perera, Ajith ............................................... 26, 43
Piqueras, Mari-Carmen .................................... 39
Rebolledo-Salgado, I. ....................................... 32
Récamier, J. ................................................ 11, 43
Rivera-Arrieta, Herzain I. ............................ 16, 43
Rodríguez-Córdoba, W. .................................... 20
Rohlén, J. .......................................................... 32
Román-Ancheyta, R. ........................................ 11
Runge, Keith ............................................... 24, 43
Sabin, John R. ............................................. 38, 43
Santamaria, R. .................................................. 23
Schaefer, Henry .......................................... 31, 43
Schneider, Barry ......................................... 13, 43
Stenger, Frank .............................................. 8, 43
Trickey, S. B. ............................................... 21, 43
Valerio-Torres, J. J............................................. 32
Varga,K. ............................................................ 34
Vela Amieva, Alberto........................................ 43
Windelius, O..................................................... 32
Wrighton, Jeffrey ............................................. 31
Wu, Y. ............................................................... 34
Yang, Wanli ...................................................... 35
Zaragoza, I.P. .............................................. 23, 44
Zhang, X.-G................................................. 27, 34