manuel azaña:

La misión de la UNIVERSIDAD es el desarrollo social, económico y cultural de la sociedad de su entorno a traves de la creación y transmisión de CONOCIMIENTOS, ofreciendo una docencia de calidad y desarrollando una investigación avanzada de acuerdo con exigentes criterios internacionales.

José Ortega y Gasset acuñó una metáfora sumamente útil para comprender intuitivamente la situación de nuestro tiempo:

La cultura es el esfuerzo permanente que un nadador realiza para mantenerse a flote.

Manuel Azaña:

Si cada español hablara de lo que sabe y solo de lo que sabe, se haría un gran silencio nacional que podríamos aprovechar para estudiar

The large investments in research and education made in The large investments in research and education made in recent years have provided Brazilian scientists with the recent years have provided Brazilian scientists with the conditions to achieve scientific excellence.conditions to achieve scientific excellence.

NATURE MATERIALS | VOL 9 | JULY 2010 |527NATURE MATERIALS | VOL 9 | JULY 2010 |527

WWW.NATURE.COM/NATUREMATERIALSWWW.NATURE.COM/NATUREMATERIALS

Nanoscience research crosses disciplines and has incorporated knowledge from many fields

W.J. Parak, ACS Nano, 4, 4333 (2010)

Theoretical and Computational Nanotechnology:

Fundaments and Applications.

Prof. Juan Andrés

Juan Andres Bort

Work address: Department of Physical and Analytical Chemistry, Universitat Jaume I,Castelló(Spain) Graduation: Chemistry, 1978, Universitat de Valencia Ph.D. dissertation: Chemistry,1982, Universitat de Valencia Current position: 1994, Full Professor, Physical Chemistry, Universitat Jaume I

ACADEMIC MANAGEMENT- Director of International relationships (2 years)- Director of the Department of Experimental Sciences (7 years)- Vice-rector of Scientific and Technological Promotion, Universitat Jaume I (5 years)

PUBLICATIONS - Articles: 305 published + 7 submitted for publication.- Books: 15 published (text books)- Book Chapters: 10 published (research)- 2 published Book as Co-editor

MAIN LINES OF RESEARCH

Electronic structure and chemical reactivity. Molecular mechanics of chemical reactions. Enzyme Catalysis: Quantum Mechanics (QM)/Molecular Mechanics(MM) and Molecular Dynamics studies. Theoretical organic, organometallic and biological chemistry. Topological analysis of electronic distribution.Electric and magnetic properties of materials. High pressure effects in materials. Growth, crystallization and formation processes in crystals. Optical properties of materials.Diffusion processes in solid state

h index= 37, more than 4600 citations.

-More than 400 communications at both national and international congresses.

-More than 20 as Invited Speaker in international congresses and 5 in national congresses.

- 5 as Chairman in international congresses and 2 in national congresses.

-15 Conferences in different Universities of Brazil, Chile, France, Italy and Sweden.

-14 Conferences in different Universities of Spain (Barcelona, Cádiz, Gerona, Granada, La Coruña, Madrid, Oviedo, País Vasco, Santiago de Compostela, Sevilla, Valencia, Zaragoza) .

- More than 40 research projects as principal research, funded by European Community, Ministerio de Educación y Ciencia, Generalitat Valenciana, Fundación Bancaixa-UJI

-Theses supervised: 18 Ph. D.

AcknowledgmentsAcknowledgmentsDr. Mario MoreiraDr. Mario MoreiraDr. Diogo VolantiDr. Diogo VolantiDr. Valeria LongoDr. Valeria LongoDr. Marcelo OrlandiDr. Marcelo OrlandiProf. Jose A. VarelaProf. Jose A. VarelaProf. Elson Longo Prof. Elson Longo Prof. Edson LeiteProf. Edson Leite(CMDCM, Sao Carlos and Araraquara, Brazil)(CMDCM, Sao Carlos and Araraquara, Brazil)

Prof. Armando BeltránProf. Armando BeltránDr. Lourdes GraciaDr. Lourdes Gracia(Universitat Jaume I)(Universitat Jaume I)

Dr. Julio Sambrano (Bauru)Dr. Julio Sambrano (Bauru)Dr. Fabricio Sensato (Sao Paulo)Dr. Fabricio Sensato (Sao Paulo)Daniel Stroppa (Campinas)Daniel Stroppa (Campinas)

Brazilian Brazilian agencies Fapesp and CNPq by the financial supportagencies Fapesp and CNPq by the financial support,.,.Research funds provided by the Research funds provided by the Ministerio de Educación y CulturaMinisterio de Educación y Cultura of the of theSpanish Government.Spanish Government.Docent Stay supported by Universitat Jaume I-Banco SantanderDocent Stay supported by Universitat Jaume I-Banco Santander

. Chapter 1. Introduction, perspectives, and aims. On the science

of simulation and modelling. Modelling at bulk, meso, and nano

scale. (2 hours).

Chapter 2. Experimental Techniques in Nanotechnology. Theory

and Experiment: “Two faces of the same coin” (2 hours).

Chapter 3. Introduction to Methods of the Classic and Quantum

Mechanics. Force Fields, Semiempirical, Plane-Wave

pseudpotential calculations. (2 hours)

Chapter 4. Intoduction to Methods and Techniques of Quantum

Chemistry, Ab initio methods, and Methods based on Density

Functional Theory (DFT). (4 hours)

Chapter 5. Visualization codes, algorithms and programs.

GAUSSIAN, CRYSTAL, and VASP. (6 hours).

. Chapter 6. Calculation of physical and chemical properties of

nanomaterials. (2 hours).

Chapter 7. Calculation of optical properties. Photoluminescence.

(3 hours).

Chapter 8. Modelization of the growth mechanism of

nanomaterials. Surface Energy and Wullf architecture (3 hours)

Chapter 9. Heterostructures Modeling. Simple and complex

metal oxides. (2 hours)

Chapter 10. Modelization of chemical reaction at surfaces.

Heterogeneous catalysis. Towards an undertanding of the

Nanocatalysis. (4 hours)

Chapter 1. Introduction, perspectives, and aims. On the science of simulation

and modelling. Modelling at bulk, meso, and nano scale.

Juan AndrésDepartamento de Química-Física y Analítica

Universitat Jaume ISpain

&CMDCM, Sao Carlos

Brazil

Sao Carlos, Octubro 2011

How How computational/theoretical computational/theoretical chemists can be useful in chemists can be useful in

the field of the field of nanoscience/nanotechnolognanoscience/nanotechnolog

y?y?

What can a What can a theoretical/computational chemist theoretical/computational chemist bring to the experimentalist activebring to the experimentalist active

in the devolopment of in the devolopment of nanoscience/nanotechnology ?nanoscience/nanotechnology ?

“It is the goal of this Course to present in one place the key features, methods, tools, and techniques of Theoretical and Computational Nanotechnology, to provide examples where Theoretical and Computational Chemistry has produced a major contribution to multidisciplinary efforts, and to point out the possibilities and opportunities for the future.”

“Maybe it is because I work on quantum mechanics, but I think that the big challenge in materials science in general as well as in Naoscience and Nanotechnology in particular is understanding how quantum mechanics influences materials at the microscopic level.”

Simulation techniques are playing an increasingly important role in the burgeoning field of nanotechnology. Arguably the nanotechnology revolution, which has seen a worldwide investment of more than $42 billion dollars over the last decade, was seeded both by developments in analytical techniques capable of characterising down to the nanoscale and by developments in computational hardware and techniques capable of modelling structures at that length scale.

Atomistic simulation (molecular mechanics and dynamics, quantum mechanics and field based approaches) has played an important role in nanoscience: predicting nanostructure and revealing mechanisms for intriguing nanoscale behaviors. Experimental nanoscience has provided a valuable source of data for the validation of simulation techniques, basis sets and force-fields. As nanoscience is increasingly turned into nanotechnologies, computer simulation methods can play a critical role.

Experimental nanoscience has provided a valuable source of data for the validation of simulation techniques, basis sets and force-fields. As nanoscience is increasingly turned into nanotechnologies, computer simulation methods can play a critical role.

An overview of some of the theoretical An overview of some of the theoretical questions that remain to be answered, questions that remain to be answered, is a useful first step towards designing is a useful first step towards designing new fundamental research programs new fundamental research programs (combining both experimental and (combining both experimental and theoretical investigations).theoretical investigations).

General Considerations 1General Considerations 1

I hope that this original approach will be I hope that this original approach will be useful to experimentalists wishing to useful to experimentalists wishing to carry out fundamental studies of carry out fundamental studies of nanostructures, and to theoreticians nanostructures, and to theoreticians who are looking for new challenges.who are looking for new challenges.


It should be emphasized that this It should be emphasized that this problem area is not just of problem area is not just of academic interest. All the academic interest. All the questions mentioned above have questions mentioned above have direct relevance for different direct relevance for different physical and chemical phenomena.physical and chemical phenomena.


This course provides an exemplary This course provides an exemplary overview of research on this topic, overview of research on this topic, from simple model systems where from simple model systems where first qualitative explanations start first qualitative explanations start to be successful, up to more to be successful, up to more realistic complex systems which realistic complex systems which are still beyond our understanding.are still beyond our understanding.


OutlineOutline

IntroductionIntroduction– Nanoscience, NanotechnologyNanoscience, Nanotechnology– HistoryHistory– Methods of Theoretical & Computational Methods of Theoretical & Computational

ChemistryChemistry– ChallengesChallenges

Nature has evolved highly complex Nature has evolved highly complex and elegant mechanisms for materials and elegant mechanisms for materials and synthesis. Living organisms and synthesis. Living organisms produce materials with physical produce materials with physical properties that still surpass those of properties that still surpass those of analogous synthetic materials with analogous synthetic materials with similar phase compositions. similar phase compositions.

Nature has long been using the Nature has long been using the bottom-up nanofabrication method to bottom-up nanofabrication method to form self-assembled nanomaterials form self-assembled nanomaterials that are much stronger and tougher that are much stronger and tougher than many man-made materials than many man-made materials formed top-down.formed top-down.

The term “nano” is derived from the Greek word for “dwarf”, “nanos”. This etymology, and its placement on the metric scale (1 nm=10-9 m), make it clear that tiny dimensions not visible to the naked eye, beyond the normal limits of our observation, are involved. Approaching it from familiar terrain may make the “nanoworld” more easily accessible (Figure 1).

Characteristic of nanoparticles, besides their small size, is their vast surface area. A simple thought experiment will serve to illustrate this concept (Figure 2). Take a cube with edges 1 cm in length—roughly the size of a sugar cube—at divide it step by step into cubes with edges 1 nm in length.

While the sum of the volumes remains the same, the numberof individual cubes and their total surface area increasesdramatically.

The surface area of the 1021 “nanocubes”, at 6000 m2, amounts to roughly the area of a football field (ca. 7000 m2)—created from a single sugar cube! Compared to an infinite three-dimensional solid (aptly expressed by the term“bulk”), with nanoparticles we may expect that their physicochemicalproperties are strongly influenced, if not indeed dominated, by the surface. Unsaturated bonding sites and unoccupied coordination sites will play a major role, compared to a highly ordered crystalline solid

A nanomaterial is commonly defined as an object with dimensions of 1–100 nm, which includes nanogels, nanofibers, nanotubes and nanoparticles (i.e. spheres, rods and cubes).

NMs can have various applications in areas such as electronics, clothing, food packaging, paint, surface modifications, additives in food packaging and drugs. It is expected that the sale of products employing nanotechnology may reach $1 trillion per year by 2015, with medical-related products alone occupying $53 billion in this market.

In August 2009, there were more than 1000 nanotechnology incorporated products marketed by 485 companies in 24 countries.

W. W. I. C. f. Scholars, Consumer Products: An Inventory of Nanotechnology-based Consumer Products Currently on theMarket, 2010, http://www.nanotechproject.org/inventories/consumer/,T. Xia, N. Li and A. E. Nel, Annu. Rev. Public Health, 2009, 30,137. C. F. Jones and D. W. Grainger, Adv. Drug Delivery Rev., 2009, 61, 438.

Nanomaterials are of immense importance in today’s modern society. The development of chemical industries, environmental protection and new-energy resources (e.g., fuel cells, lithium ion batteries) have long relied on nanomaterials with exceptional properties.

The fields of catalysis, electrocatalysis, photocatalysis and photoelectricity are all examples of where nanotechnology is impacting on current science.1–4

1 C. Burda, X. B. Chen, R. Narayanan and M. A. El-Sayed, Chem. Rev., 2005, 105, 1025.

2 M. Haruta, CATTECH, 2002, 6, 102.

3 D. Astruc, F. Lu and J. R. Aranzaes, Angew. Chem., Int. Ed., 2005, 44, 7852.

4 M. C. Daniel and D. Astruc, Chem. Rev., 2004, 104, 293.

As particle dimensions reduce towards the nanoscale, the surface-to-volume ratio proportionally increases and smallsize effects associated with nanoparticles become more pronounced.

Understanding the nanoscale topography of surface sites, such as terraces, steps, kinks, adatoms and vacancies, and their effects on catalytic and other physicochemical properties is the key to designing nanoscale functional materials by nanotechnology.5–7

5 G. A. Somorjai, Science, 1978, 201, 489.6 F. Tao and M. Salmeron, Science, 2011, 331, 171.7 D. L. Feldheim, Science, 2007, 316, 699.

The performance of nanocrystals used as catalysts depends strongly on the surface structure of facets enclosing the crystals. Thermodynamics usually ensures that crystal facets evolve to have the lowest surface energy during the crystal growth process. For a pure metal, the surface energy relies on coordination numbers (CNs) of surface atoms as well as their density. For example, it increases in the order of {111} < {100} < {110} < {hkl} on a face-centered cubic (fcc) metal, where {hkl} represents high-index planes with at least one Miller index larger than 1.8,9

8 Z. L. Wang, J. Phys. Chem. B, 2000, 104, 1153.9 Y. N. Wen and H. M. Zhang, Solid State Commun., 2007, 144,163.

For a metal oxide, the surface energy increases with increasing density of dangling bonds. Generally, high-energy surfaces have an open surface structure and possess exceptional properties.

Long-term fundamental studies in surface science have shown that Pt high-index planes with open surface structure exhibit much higher reactivity thanthat of (111) or (100) low-index planes, because high-index planes have a large density of low-coordinated atoms situated on steps and kinks, with high reactivity required for high catalytic activity.10–12

10 N. P. Lebedeva, M. T. M. Koper, J. M. Feliu and R. A. van Santen, J. Phys. Chem. B, 2002, 106, 12938.

11 S. L. Bernasek and G. A. Somorjai, Surf. Sci., 1975, 48, 204.

12 S. G. Sun, A. C. Chen, T. S. Huang, J. B. Li and Z. W. Tian, J. Electroanal. Chem., 1992, 340, 213.

More importantly, on high-index planes, there exist short-range steric sites (such as ‘‘chair’’ sites) that are considered as active sites and consist of the combination of several (typical 5–6) step and terrace atoms.13,14

13 R. A. Van Santen, Acc. Chem. Res., 2009, 42, 57.

14 N. Tian, Z. Y. Zhou and S. G. Sun, J. Phys. Chem. C, 2008, 112, 19801.

Due to synergistic effect between step and terrace atoms, steric sites usually serve as catalytically active sites. Besides, open-structure surfaces also play a very important role in the charging/discharging process of lithium ion batteries. They can provide parallel channels, where Li+ ions are able to intercalate through the surface with the least resistance compared to other crystal plane orientations.15 This favors fast ion transfer between surface and interior.

15 G. Z. Wei, X. Lu, F. S. Ke, L. Huang, J. T. Li, Z. X. Wang, Z. Y. Zhou and S. G. Sun, Adv. Mater., 2010, 22, 4364.

Normally, nanocrystals with low surface energy such as those formed under normal conditions usually have low catalytic activities. Those with high surface energies are known to possess enhanced catalytic properties.

The goal here is to create nanocrystal catalysts which have high surface energy facets. Unfortunately, this presents a big challenging. When a crystal grows, different facets grow with different rates. High-energy facets typically have higher growth rates than low-energy facets. Overall, the final crystal shape is dominated by the slow-growth facets that have low surface energy.16

16 H. E. Buckley, Crystal Growth, Wiley, New York, 1951.

Remarkably, substantial progress has been made in overcoming the obstacle to form nanocrystals with high-energy facets in recent years.30–32

30 N. Tian, Z. Y. Zhou, S. G. Sun, Y. Ding and Z. L. Wang, Science, 2007, 316, 732.

31 H. G. Yang, C. H. Sun, S. Z. Qiao, J. Zou, G. Liu, S. C. Smith, H. M. Cheng and G. Q. Lu, Nature, 2008, 453, 638.

32 Z. Y. Jiang, Q. Kuang, Z. X. Xie and L. S. Zheng, Adv. Funct. Mater., 2010, 20, 3634.

Although there are several excellent reviews about shape controlled synthesis of metal nanocrystals, they mainly describe nanocrystals with low-energy facets.28,33,34

28 Z. M. Peng and H. Yang, Nano Today, 2009, 4, 143.

33 A. R. Tao, S. Habas and P. D. Yang, Small, 2008, 4, 310.

34 Y. Xia, Y. J. Xiong, B. Lim and S. E. Skrabalak, Angew. Chem.,Int. Ed., 2009, 48, 60.

In this review, after a brief introduction of the relationship between surface structure and crystal shapes, we focus on the recent progress made in shape-controlled synthesis of metal nanocrystals with high-energy facets and open surface structure, including high-index facets and {110} facets, especially electrochemically shape-controlled synthesis of Pt-group metal nanocrystals.

Z.-Y. Zhou, N. Tian, J.-T. Li, I. Broadwell and S.-G. Sun, Nanomaterials of high surface energy with exceptional properties in catalysis and energy storage, Chem. Soc. Rev., DOI: 10.1039/c0cs00176g

Engineering the shapes of semiconducting functional materials to desirable morphologies has long been actively pursued. This is because many applications such as heterogeneous catalysis, gas sensing and ion detecting, molecule adsorption, energy conversion and storage are very sensitive to surface atomic structures, which can be finely tailored by morphology control.

From the intensive studies on morphology-controlled materials in the past decades, significant advancements in this area have been achieved.1–29

1 S. E. Habas, H. Lee, V. Radmilovic, G. A. Somorjai and P. Yang, Nat. Mater., 2007, 6, 692.2 C. K. Tsung, J. N. Kuhn, W. Y. Huang, C. Aliaga, L. I. Hung, G. A. Somorjai and P. D. Yang, J. Am. Chem. Soc., 2009, 131, 5816.3 A. Tao, P. Sinsermsuksakul and P. D. Yang, Angew. Chem., Int. Ed., 2006, 45, 4597.4 A. I. Hochbaum and P. D. Yang, Chem. Rev., 2010, 110, 527.5 Y. Xia, Y. J. Xiong, B. Lim and S. E. Skrabalak, Angew. Chem., Int. Ed., 2008, 48, 60.6 B. Wiley, Y. G. Sun, J. Y. Chen, H. Cang, Z. Y. Li, X. D. Li and Y. N. Xia, MRS Bull., 2011, 30, 356.7 B. Lim, H. Kobayashi, T. Yu, J. G. Wang, M. J. Kim, Z. Y. Li, M. Rycenga and Y. Xia, J. Am. Chem. Soc., 2010, 132, 2506.8 Y. J. Xiong and Y. N. Xia, Adv. Mater., 2007, 19, 3385.9 B. Wiley, Y. G. Sun, B. Mayers and Y. N. Xia, Chem.–Eur. J., 2005, 11, 454.

10 B. Sadtler, D. O. Demchenko, H. Zheng, S. M. Hughes, M. G. Merkle, U. Dahmen, L. W. Wang and A. P. Alivisatos, J. Am. Chem. Soc., 2009, 131, 5285.11 Y. D. Yin, C. Erdonmez, S. Aloni and A. P. Alivisatos, J. Am. Chem. Soc., 2006, 128, 12671.12 X. J. Feng, J. Zhai and L. Jiang, Angew. Chem., Int. Ed., 2005, 44, 5115.13 X. L. Li, Q. Peng, J. X. Yi, X. Wang and Y. D. Li, Chem.–Eur. J.,2006, 12, 2383.14 X. Wang, J. Zhuang, Q. Peng and Y. D. Li, Nature, 2005, 437, 121.15 Y. G. Sun and Y. N. Xia, Science, 2002, 298, 2176.16 F. Wang, Y. Han, C. S. Lim, Y. H. Lu, J. Wang, J. Xu, H. Y. Chen, C. Zhang, M. H. Hong and X. G. Liu, Nature, 2010, 463, 1061.17 B. Lim, M. J. Jiang, P. H. C. Camargo, E. C. Cho, J. Tao, X. M. Lu, Y. M. Zhu and Y. A. Xia, Science, 2009, 324, 1302.18 N. Tian, Z. Y. Zhou, S. G. Sun, Y. Ding and Z. L. Wang, Science, 2007, 316, 732.

19 X. W. Xie, Y. Li, Z. Q. Liu, M. Haruta and W. J. Shen, Nature, 2009, 458, 746.20 X. D. Feng, D. C. Sayle, Z. L. Wang, M. S. Paras, B. Santora, A. C. Sutorik, T. X. T. Sayle, Y. Yang, Y. Ding, X. D. Wang and Y. S. Her, Science, 2006, 312, 1504.21 H. G. Yang, C. H. Sun, S. Z. Qiao, J. Zou, G. Liu, S. C. Smith, H. M. Cheng and G. Q. Lu, Nature, 2008, 453, 638.22 X. G. Peng, L. Manna, W. D. Yang, J. Wickham, E. Scher, A. Kadavanich and A. P. Alivisatos, Nature, 2000, 404, 59.23 J. H. Xiang, S. H. Yu, B. H. Liu, Y. Xu, X. Gen and L. Ren, Inorg. Chem. Commun., 2004, 7, 572.24 C. Z. Wu and Y. Xie, Chem. Commun., 2009, 5943.25 X. G. Han, M. S. Jin, S. F. Xie, Q. Kuang, Z. Y. Jiang, Y. Q. Jiang, Z. X. Xie and L. S. Zheng, Angew. Chem., Int. Ed., 2009, 48, 9180.26 C. Burda, X. B. Chen, R. Narayanan and M. A. El-Sayed, Chem. Rev., 2005, 105, 1025.27 X. Chen and S. S. Mao, Chem. Rev., 2007, 107, 2891.28 H. C. Zeng, J. Mater. Chem., 2006, 16, 649.29 H. G. Yang and H. C. Zeng, Angew. Chem., Int. Ed., 2004, 43, 5930.

Crystal facet engineering of semiconductor photocatalysts: motivations, advances and unique properties

G. Liu, J. C. Yu, G. Q. Luc and H.-M. Cheng.Chem. Comm, DOI: 10.1039/c1cc10665a

Dominance of broken bonds and nonbonding electrons at the Dominance of broken bonds and nonbonding electrons at the nanoscale, nanoscale, Chang Q Sun, Nanoscale, 2010Chang Q Sun, Nanoscale, 2010

Materials at the nanoscale demonstrate novel properties of two types.Materials at the nanoscale demonstrate novel properties of two types.

One is the size and shape induced tunability of the otherwise constantOne is the size and shape induced tunability of the otherwise constant

quantities associated with bulky species. For example, the elasticquantities associated with bulky species. For example, the elastic

modulus, dielectric constant, conductivity, melting point, etc, of amodulus, dielectric constant, conductivity, melting point, etc, of a

substance no longer remain constant but change with its shape andsubstance no longer remain constant but change with its shape and

size; the other is the emergence of completely new properties thatsize; the other is the emergence of completely new properties that

cannot be seen from the bulk such as the extraordinary high capabilitycannot be seen from the bulk such as the extraordinary high capability

for catalysis, nonmagnetic–magnetic and conductor–insulatorfor catalysis, nonmagnetic–magnetic and conductor–insulator

transitions. These two entities form the foundations of nanoscience andtransitions. These two entities form the foundations of nanoscience and

Nanotechnology that has been recognized as one of the key drivers ofNanotechnology that has been recognized as one of the key drivers of

science, technology and economics in the 21science, technology and economics in the 21st st century.century.

Originating from the fields of physics, Originating from the fields of physics, chemistry, materials science, and chemistry, materials science, and chemical engineering, this area of study chemical engineering, this area of study is now often referred to as nanoscience.is now often referred to as nanoscience.

Nanoscience 1Nanoscience 1

Nanostructured materials such as nanoparticles, nanotubes, nanowires (nanorods), nanoribbons (nanobelts), nanotapes, nanorings, nanoplates, nanotriangles, nanosheets, nanoballs and nanohelices,


ALL IS NANO !ALL IS NANO !

……..have attracted extensive ..have attracted extensive attention due to their properties attention due to their properties with important and potential with important and potential applications in constructing applications in constructing nanoscaled electronic and opto-nanoscaled electronic and opto-electronic devices, gas sensors, electronic devices, gas sensors, catalysts, and thin growth.catalysts, and thin growth.


Feymann, R. P. Eng. Sci. 23, 22 (1960).

“The principle of Physics as far as I can see, do not speak against the possibility of maneuvering things atom by atom.”

Where are we?

TODAY THE QUEST FOR NOVEL MATERIALS WITH DISTINCT PROPERTIES TODAY THE QUEST FOR NOVEL MATERIALS WITH DISTINCT PROPERTIES FOR CRITICAL TECHNOLOGICAL APPLICATIONS HAS MOTIVATED A FOR CRITICAL TECHNOLOGICAL APPLICATIONS HAS MOTIVATED A

CONSITENT EFFORT IN BETTER UNDERSTANDING SOLID-STATE CONSITENT EFFORT IN BETTER UNDERSTANDING SOLID-STATE PROCESSES, PROCESSES, BOTH EXPERIMENTALLY AND FROM THEORYBOTH EXPERIMENTALLY AND FROM THEORY

THE PROGRESS OF THE PAST DECADES ON NANOMATERIALS HAVE THE PROGRESS OF THE PAST DECADES ON NANOMATERIALS HAVE SHOWN THAT BULK PROPERTIES BREAK DOWN ON CROSSING LOWER SIZE SHOWN THAT BULK PROPERTIES BREAK DOWN ON CROSSING LOWER SIZE

LIMITS, UNFOLDING LIMITS, UNFOLDING A RICH SET OF NEW PHYSICAL AND CHEMICAL A RICH SET OF NEW PHYSICAL AND CHEMICAL PROPERTIES AND OPENING NEW SYNTHETIC ROUTESPROPERTIES AND OPENING NEW SYNTHETIC ROUTES

FOR THE SYNTHETIC EFFORTS TO FULLY TAKE ADVANTAGE OF SUCH FOR THE SYNTHETIC EFFORTS TO FULLY TAKE ADVANTAGE OF SUCH PECULIAR PROPERTIES, PECULIAR PROPERTIES, A PRECISE AND FIRM ATOMISTIC UNDERSTANDING A PRECISE AND FIRM ATOMISTIC UNDERSTANDING

IS MANDATORYIS MANDATORY

SIMULATIONS OF REAL MATERIALSSIMULATIONS OF REAL MATERIALS UNDER CONDITION CORRESPONDING UNDER CONDITION CORRESPONDING TO THE EXPERIMENTS ARE SHEDDING LIGHT ONTO YET ELUSIVE ASPECTSTO THE EXPERIMENTS ARE SHEDDING LIGHT ONTO YET ELUSIVE ASPECTS

ACCORDINGLY, A NEW WAY OF BRIGING TOGETHER ACCORDINGLY, A NEW WAY OF BRIGING TOGETHER THEORYTHEORY, , IMPLEMENTATION OF IMPLEMENTATION OF SIMULATIONSIMULATION STRATEGIES AS A POWEFUL SUPPORT STRATEGIES AS A POWEFUL SUPPORT

TO THE TO THE EXPERIMENTSEXPERIMENTS IS EMERGING. IS EMERGING.

Where are we?THE DEVELOPMENT AND IMPLEMENTATION OF THE DEVELOPMENT AND IMPLEMENTATION OF FIRST-FIRST-PRINCIPLE METHODS AND TECHNIQUESPRINCIPLE METHODS AND TECHNIQUES ALLOW TO CARRY ALLOW TO CARRY OUT CALCULATIONS TO QUANTITATIVELY PREDICT AND OUT CALCULATIONS TO QUANTITATIVELY PREDICT AND EXPLAIN EXPLAIN THE PHYSICAL AND CHEMICAL PROPERTIES OF THE PHYSICAL AND CHEMICAL PROPERTIES OF MATERIALSMATERIALS..

ELECTRONIC STRUCTURE THEORYELECTRONIC STRUCTURE THEORY PROVIDES BOTH PROVIDES BOTH CONCEPTUAL UNDERSTANDING AND COMPUTATIONAL CONCEPTUAL UNDERSTANDING AND COMPUTATIONAL TOOLS TO CALCULATE IT.TOOLS TO CALCULATE IT.

ADVANCE IN ADVANCE IN THEORETICAL METHODS AND TECHNIQUESTHEORETICAL METHODS AND TECHNIQUES AS AS WELL AS WELL AS COMPUTATIONAL POWERCOMPUTATIONAL POWER HAVE HAD A HAVE HAD A TREMENDOUS IMPACT IN TREMENDOUS IMPACT IN MATERIALS SCIENCEMATERIALS SCIENCE

OF COURSE, OF COURSE, THEORETICALTHEORETICAL GUIDANCE NEEDS TO BE USED GUIDANCE NEEDS TO BE USED IN A IN A COOPERATIVILY COOPERATIVILY MANNER WITH THE ACCUMULATED MANNER WITH THE ACCUMULATED EXPERIENCE OF EXPERIENCE OF EXPERIMENTALEXPERIMENTAL EXPLORERS. EXPLORERS.

Where are we?

DURING THE LAST YEARS DURING THE LAST YEARS ELECTRONIC ELECTRONIC STRUCTURE THEORYSTRUCTURE THEORY DEVELOPED FROM A DEVELOPED FROM A DESCRIPTIVE TO AN ANALYTICALDESCRIPTIVE TO AN ANALYTICAL TOOL AND IS TOOL AND IS NOW AN INTEGRAL PART OF RESEARCH WITH NOW AN INTEGRAL PART OF RESEARCH WITH IMPORTANT CONSEQUENCES:IMPORTANT CONSEQUENCES:

1. FACILITING THE INTERPRETATION AND 1. FACILITING THE INTERPRETATION AND RATIONALIZATION OF EXPERIMENTAL RESULTSRATIONALIZATION OF EXPERIMENTAL RESULTS

2. HELPING TO UNCOVER ESSENTIAL CRYSTAL 2. HELPING TO UNCOVER ESSENTIAL CRYSTAL STRUCTURE-PROPERTY RELATIONSHIPSSTRUCTURE-PROPERTY RELATIONSHIPS

3. DIRECTING FURTHER3. DIRECTING FURTHER

Computer simulation methods in physical chemistry: Large molecules, fluids and solids

Annual Meeting of the Deutsche Bunsen-Gesellschaft für Physikalische Chemie, Stuttgart, May 24-26, 2001

“Science is undergoing a structural transition from two broad methodologies to three, namely from experimental and theoretical science to include the additional category of computational and information science. A comparable example of such a change occurred with the development of systematic experience science at the time of Galileo” — Advanced Scientific Computing Committee of the US National Science Foundation.

J. Brickmann and J. Sauer, Phys. Chem. Chem. Phys., 2001, 3

In silico methods are a valid tool for analysing the properties of materials and interest in computational modelling techniques to predict their physical/chemical properties is constantly growing.

ExperimentRealWord Theory

Model of the Word

ExperimentalData

Simulation

ClassificationAbstraction

SimplificationApproximation Generalization

PredictionsComparing is testing

ApplyingTheoretical Methods,

Computing Techniquesand Mathematical

Algorithms

Three Important Turns in Science

Modified from: Modified from:

van Gunsteren et al., Angew. Chem. Int. Ed. Engl, 45, 4064 (2006)van Gunsteren et al., Angew. Chem. Int. Ed. Engl, 45, 4064 (2006)

Thales 600 BC Thales 600 BC ObserveObserveModelModel

Galileo 1500 BC Model Galileo 1500 BC Model Design Experiment Design Experiment Observe ObserveModelModel

Rahman Rahman

and Parrinello Mimic Reality on a Computer and Parrinello Mimic Reality on a Computer Observe ObserveModelModel

““Crystal Structure and Pair Potentials. A Molecular Dynamics Crystal Structure and Pair Potentials. A Molecular Dynamics Study”Study”

Physical Review Letters, 45, 1196 (1980)Physical Review Letters, 45, 1196 (1980)

“Computations on complex systems are, in my opinion, the current frontier of theoretical chemistry”

D. G. TruhlarMolecular Modeling of Complex Chemical Systems

J. Am. Chem. Soc., 2008, 130, 16824-16827

56

““THE ETERNAL MISTERY OF THE THE ETERNAL MISTERY OF THE WORLD IS ITS COMPREHENSIBILITY. WORLD IS ITS COMPREHENSIBILITY. THE FACT THAT IT IS THE FACT THAT IT IS COMPREHENSIBLE IS A MIRACLE”COMPREHENSIBLE IS A MIRACLE”

ALBERT EINSTEINALBERT EINSTEIN

CLUSTER-ASSEMBLED MATERIALSCLUSTER-ASSEMBLED MATERIALS

Fullerenes, atomic clusters, and larger inorganic nanocrystals can be used as assembly elements for creating materials with tailored properties.

S. A. Claridge, A. W. Castleman, S. N. Khanna, C. B. Murray, A. Sen, P. S. Weiss, ACS Nano 2009, 3, 244. 58

SHAPE-CONTROLLED SHAPE-CONTROLLED SYNTHESIS OF METAL SYNTHESIS OF METAL

NANOCRYSTALSNANOCRYSTALS

Reaction pathways that lead to fcc metal nanocrystals

having different shapes. First, a precursor is reduced or decomposed to form the

nuclei (small clusters). Once the nuclei have grown past a

certain size, they become seeds with a single-crystal, singly twinned, or multiply

twinned structure. If stacking faults are introduced, then

plate-like seeds will be formed.

Y. Xia, Y. Xiong, B. Lim, Sara E. Skrabalak, Angew. Chem. Int. Ed. 2009, 48, 60.

59

J. Phys. Chem. C 2008, 112, 18303 V. H. Grassian

Microscopic and macroscopic behaviors of nanoparticles depend on a number of a number of important characteristics and properties

VOL. 3 ▪ NO. 4 ▪ 762 ▪ 2009

A. Greenberg

The world today is facing increasing energy demands and simultaneously demand for cleaner and more environmentally friendly technologies.

- Bérube, V.; Radtke, G.; Desselhaus, M.; Chen, G. Size Effects on the Hydrogen Storage Properties of Nanostructured Metal Hydrides: A Review. Int. J. Energy Res. 2007, 31, 637.- Bérube, V.; Chen, G.; Dresselhaus, M. S. Impact of Nanostructuring on the Enthalpy of Formation of Metal Hydrides. Int. J. Hydrogen Energy 2008, 33, 4122.Schlapbach, L.; Zu¨ ttel, A. Hydrogen-Storage Materials forMobile Applications. Nature 2001, 414, 353.- Eberle, U.; Felderhoff, M.; Schüth, F. Chemical and Physical Solutions for Hydrogen Storage. Angew. Chem., Int. Ed. 2009, 48, 6608.- Orimo, S.; Nakamori, Y.; Eliseo, J. R.; Zuüttel, A.; Jensen, C. M. Complex Hydrides for Hydrogen Storage. Chem. Rev. 2007,107, 4111.- Dornheim, M.; Eigen, N.; Barkhordarian, G.; Klassen, T.; Bormann, R. Tailoring Hydrogen Storage Materials towards Application. Adv. Eng. Mater. 2006, 8, 377.

The development of new nanomaterials is expected to have a major impact on the development of novel sustainable energy technologies.

Nanotechnology is currently undergoing an impressive expansion in material science research and development of systems that have novel properties due to their small size.

Most of the research efforts have been focused on applications, while the implications efforts (i.e., environmental health and safety) have lagged behind.

As a consequence, the success of nanotechnology will require assurances that the products being developed are safe from an environmental, health, and safety standpoint.

D. B. Warheit, Nano Letters, 2010

These concerns have led to a debate among governmental agencies and advocacy groups on whether implementation of special regulations should be required for commercialization of products containing nanomaterials.

Therefore the assessments of nanomaterial-related health risks must be accurate and verifiable.

D, B. Warheit, Nano Letters, 2010

Evaluations of human health and ecological implications of nanoparticle exposures will be required to attain full commercialization potential.

D. B. Warheit, Nano Letters, 2010

The relative dearth of substantive hazard data on nanomaterials, concomitant with an abundance of high-dose, in vitro cellular findings has created a perception that the vast majority of nanoparticles are highly toxic.

Schematic showing the evolution of modern surface science

Gabor A. Somorjai and Jeong Y. Park

Examples

InIn22OO33 Nanoparticles Nanoparticles Nanoribbons – Nanobelts – NanosheetsNanoribbons – Nanobelts – NanosheetsGaOGaO

A. Murali et al. Nano Letters 1 (2001) 287.Z.R. Dai et al., J. Phys. Chem. B 106 (2002) 902.

Examples

CC6060 Fullerene Fullerene

http://www.photon.t.u-tokyo.ac.jp/~maruyama/fticr/ft-icr.html

Examples

Au55 Nanowires on SiOAu55 Nanowires on SiO22Nanotapes CoNanotapes Co0.050.05TiTi0.950.95OO22@SnO@SnO22

N. Lu et al., Nano Letters, 2 (2002) 1097. R. He et al. Nano Letters 2 (2002) 109.

Examples

Carbon NanotubesCarbon Nanotubes

NanohelicesNanohelicesLefthanded Ag helicesLefthanded Ag helices

A. Koshio et al., Nano Letters 2 (2002) 995. C. Zhan et al., Langmiur, 19 (2003) 9440.

Examples

NanotrianglesNanotriangles NanosheetsNanosheets

N. Pinna et al. Langmuir, 17 (2001) 7982. S.-H. Yu et al. Adv. Mater. 7 (1995) 607.

Examples

Fe NanorodsFe NanorodsNi NanoringsNi Nanorings

S-J. Park, J. Am. Chem.Soc. 122 (2000) 8581 K.L. Hobbs et al., Nano Letters, 4 (2004) 167

and……

Examples

Y. B. Li et al, Appl. Phys. Lett. 82 (2003) 1962.

…MoS2 nanoflowers

Nanoscience, Nanotechnology, and Chemistry G. M. Whitesides, Small 2005, 1, 172

Nanoscience is now a thread woven into many fields of science. Nanotechnology—certainly evolutionary, and perhaps evolutionary—will emerge from it. Chemistry will play a role; whether this role is supporting or leading will depend in part on how the field develops and what opportunities emerge, and in part on how imaginative and aggressive chemists and chemical engineers are, or become, in finding their place in it.

Since there are few new, high-margin markets open to the chemicalindustry, it may need to move downstream— uncomfortable though itmay be to do so—in nanotechnology (or other emerging areas) if it isnot to stagnate technically and financially. Competition in new marketsrequires agility, and the ability to move quickly to capture new opportunities is always a difficult trick. It will be particularly difficult foran industry that, for some decades, has not been rewarded forembracing new ideas or for accomplishing new tricks, and that, throughlack of practice, has become unaccustomed to doing so.

From here the nanotechnology is achieved

Nanomaterials with specific properties are obtained

Cluster and nanoparticle characterization is Cluster and nanoparticle characterization is becoming technologically possible and opens new becoming technologically possible and opens new possibilities in the developments of materials which possibilities in the developments of materials which could improve the physical and chemical propertiescould improve the physical and chemical properties

New nanocompounds that could be useful in a New nanocompounds that could be useful in a broader way than their bulk counterparts might be broader way than their bulk counterparts might be createdcreated

Nanotechnology 1Nanotechnology 1

Nanotechnology has Nanotechnology has experienced a rapid growth experienced a rapid growth recently because nanoparticles recently because nanoparticles exhibit physical and chemical exhibit physical and chemical properties that are quite properties that are quite different from those of the different from those of the bulk solidbulk solid


The field of nanotechnology The field of nanotechnology continues to advance at a continues to advance at a breathtaking pace, propelled breathtaking pace, propelled by the discovery of new by the discovery of new material, new devices, and new material, new devices, and new phenomena.phenomena.


Nano-scale Nano-scale mattermatter

Nature: Nature:

- Novel and emergent - Novel and emergent phenomenaphenomena

- Reduced time and time scale- Reduced time and time scale

- No merely scale down - No merely scale down

CMDCM, Sao Carlos

NANOARTENANOARTE

http://br.youtube.comhttp://br.youtube.com

R.FeynmanR.Feynman

Richard Feynman’s visionary lecture,

http://www.its.caltech.edu/feynman/plenty.html

‘‘There is Plenty of Room at the American Physical Society meeting at Caltech on December 29th 1959, is often quoted as giving birth to the concept of nanotechnology: controlling matter at the nanometer length-scale. It is a highly readable, but remarkably prescient account of the promise of nanoscience and technology and well worth reading. There is plenty of room at the bottom”

R.FeynmanR.Feynman

The key point of the talk is that the nanoscale is small enough for extreme minimization, but large enough (hence ‘‘there is plenty of room’’) to accommodate sufficient atoms to produce interesting complexity, if we could just learn how to control it. Nanotechnology also opens a new playground for scientists, a terra incognita with enormous possibilities, and there is plenty of room for multitudes of scientists to stretch their imaginations.

“There is plenty of room at the bottom”.R. P. Feynman, Eng. Sci. 1960, 23, 22.

No doubt, we can add “still” and “tremendous”.

Small is differentSmall is different

M.A. El-Sayed Acc. Chem. Res. (2004)M.A. El-Sayed Acc. Chem. Res. (2004)

Shape-, Size-, and Composition-Shape-, Size-, and Composition-Dependent Properties of Some Dependent Properties of Some Colloidal Semiconductor Colloidal Semiconductor NanocrystalsNanocrystals

As the size of material As the size of material becomes equal to or falls becomes equal to or falls below the nanometer length below the nanometer length scale that characterizes the scale that characterizes the motion of its electrons and motion of its electrons and thus its properties, the latter thus its properties, the latter become sensitive not only to become sensitive not only to the size but also to the shape the size but also to the shape and composition of the and composition of the particles.particles.

“ “The behavior of large and complex The behavior of large and complex aggregates of elementary particles, it aggregates of elementary particles, it turns out, is not to be understood turns out, is not to be understood in in terms of a simple extrapolation of the terms of a simple extrapolation of the properties of a few particlesproperties of a few particles. Instead, . Instead, at at each level of complexityeach level of complexity entirely new entirely new properties appear, and the properties appear, and the undestanding of the new behaviors undestanding of the new behaviors requires research which I think is a requires research which I think is a fundamental in its nature as any other”fundamental in its nature as any other”

P. W. AnderssonP. W. Andersson

“ “At each stage entirely At each stage entirely new laws, concepts, new laws, concepts, and generalizations are necessaryand generalizations are necessary, requiring , requiring inspirationinspiration and and creativitycreativity to just as great a to just as great a degree as in the previous one”degree as in the previous one”

P. W. P. W. AnderssonAndersson

Nanomaterials, nanostructures, nanostructured materials, nanoimprint, nanobiotechnology, nanophysics, nanochemistry, radical nanotechnology, nanosciences, nanooptics, nanoelectronics, nanorobotics, nanosoldiers, nanomedecine, nanoeconomy, nanobusiness, nanolawyer, nanoethics to name a few of the nanos.

We need a clear definition of all these burgeoning fields for the sake of the grant attribution, for the sake of research program definition, and to avoid everyone being lost in so many nanos.

To be nano or not to be nano? C. Joachim, Nature Materials, 4, 107 (2005)

Over the last few decades, the field of nanotechnology has grown from a laboratory novelty into a burgeoning industry. This is a direct result of the new phenomena that are exhibited a conventional materials are confined to dimensions less than a few hundred nanometers.

Quantum confinement is another unique property that exists only in the nanoscale size regime.

Quantum confinement occurs in semiconductors when their size is restricted to dimensions less than or equal to the bulk Bohr diameter of an exciton (a bound electron and hole pair) in that material.

Brus, L. E. J. Chem. Phys. 1984, 80, 4403-4408. Steigerwald, M. L.; Brus, L. E. Acc. Chem. Res. 1990, 23, 183-188.

When a photon with energy equal to or greater than the band gap energy is absorbed by a semiconductor nanocrystal, the resultant photogenerated electron and hole pair are confined within the crystal lattice at a distance less than the thermodynamic quilibrium distance in the same bulk semiconductor, which can be approximated by the exciton bulk Bohr diameter.

Much like the ‘particle in a box’ approximation, as a nanocrystal’s diameter decreases the band gap energy increases due to the increased confinement.

This energetic size dependence allows the tuning of the band gap related absorption and emission simply by changing the diameter of the nanocrystal.

Kippeny, T. C.; Swafford, L. A.; Rosenthal, S. J.

J. Chem. Ed. 2002, 79, 1094-1100.

Nanoscience, nanotechnology, nanoparticles and nanostructures are among the most widely used terms in the modern scientific and technological literature.

The field of nanoscience and nanotechnology (NST) is growing very rapidly. NST are believed to lead to dramatic modifications of many of our activities: technologies of information and communication, medicine, materials, space, energy, water, etc. Although many fundamental aspects remain to be studied, it is often claimed that NST should be introduced in the curricula of scientists and engineers.

When looking at those curricula, it turns out that some fundamental aspects might be taught in various lectures. Indeed, NST include elements of mechanics, termodynamics, electricity, quantum mechanics, etc. Scaling laws may be used to understand the differences between the macro-, micro- and nanoworlds.

As defined by the Royal Society: nanoscience is the study of phenomena and manipulation of materials at atomic, molecular and macromolecular scales, where properties differ significantly from those at the larger scale. Nanotechnologies are the design, characterization, production and application of structures, devices and systems by controlling shape and size at the nanometre scale.

The properties of materials can be different at the nanoscale for two main reasons.

First, nanomaterials have a relatively large surface area when compared to the same mass of material produced in a larger form. This can make materials more chemically reactive (in some cases materials that are inert in their larger form are reactive when produced in their nanoscale form), and affect their strength or electrical properties.

Second, quantum effects can begin to dominate the behaviour of matter at the nanoscale particularly at the lower end affecting the optical, electrical and magnetic behaviour of materials.

Materials can be produced that are nanoscale in one dimension (for instance, very thin surface coatings), in two dimensions (for example, nanowires and nanotubes) or in all three dimensions (for example, nanoparticles).

Whilst recent developments in nanotechnologies and nanosciences have raised high hopes for a potential new industrial revolution [1], they have at the same time raised a number of safety, ethical, policy and regulatory questions [2,3]. With over one thousand nano-enabled consumer products reported to be already available globally [4], …

… and many more in the R&D pipeline, it may seem strange that discussions are still going on to agree on a common definition of a nanomaterial that can be used by the producers, the users, and the regulators alike. Although a number of definitions are currently available, a practicable and unambiguous definition of a nanomaterial is yet to emerge.

It is known that the conventional physicochemical rules may not be fully applicable at the nano-scale, and may be different from those of bulk equivalents. Such ‘nano’- related features of nanomaterials (ENMs) derive from a number of parameters, such as size, shape, specific surface area, surface chemistry, etc.

Where a definition has legal consequences, legislators prefer a simple and clear-cut distinction, i.e. what is legislated or authorised and what is not.

A quick glance at the existing definitions of nanomaterials (Table 1) shows that there is a virtual consensus on that a nanomaterial is a material, which is intentionally produced in the nano-scale (i.e. approximately 1—100 nm), to have a specific property or a composition.

The 100nm size boundary used in these definitions, however, only loosely refers to the nano-scale around which the properties of materials are likely to change significantly from conventional equivalents

In reality, there is no clear size cut-off for this phenomenon, and the 100nm boundary appears to have no solid scientific basis. A change in properties of particulate materials in relation to particle size is essentially a continuum, which although more likely to happen below 100nm size range, does not preclude this happening for some materials at sizes above 100 nm.

‘Can I believe modelling?’… is a question often asked by both experiment and theoretical researchers. Answering it requires informed understanding of the strengths and limitations of current computational molecular modelling and simulation methods, and their ranges of application.

Knee-jerk scepticism of all modelling is sometimes encountered among experimentalists even today; equally misguided is a blind acceptance of modelling results without critical analysis. However, demonstrations of the practical contribution made by molecular modelling have led to a growing recognition of its worth. This is a fertile and growing area, with exciting opportunities and an enormous range of potential applications. It is crucial for the molecular modeller to understand the issues of interest to experimentalists, the complexity of chemical systems and how to tackle them effectively by modelling.

Modelling Modelling Modelling Modelling

We break modelling down into four broad categories:

Figure shows roughly the size of systems that are modelled in each domain and the length of time for which a dynamic process can be simulated. Generally speaking, as one moves to larger systems, more approximations are employed and the methods are less precise.

On the accuracy of modelling and calculations On the accuracy of modelling and calculations On the accuracy of modelling and calculations On the accuracy of modelling and calculations

quantum mechanical,

molecular mechanical,

mesoscale,

and bulk scale.

G. Fitzgerald et al. Materials Modeling from Quantum Mechanics to the MesoscaleCMES, vol.24, no.3, pp.169-183, 2008

Seconds

Microseconds

Nanoseconds

Picoseconds

Femtoseconds

1nm 10nm 100nm 1microm

Time

Distance

Quantum

Molecular

Mesoscale

Bulk Scale

Electronic structure of methane

Molecular structure of polymer

Self-organized nanostructure

Finite element

analysis


However, even with present-day computers and algorithms, we cannot solve the many particle Schrödinger equation exactly; inevitably some error is introduced in approximating the solutions of this equation. Thus, the accuracy of quantum chemical calculations is of critical importance.

F. Neese, A. Hansen, F. Wennmohs, and S. GrimmAccurate Theoretical Chemistry with Coupled Pair Models

Acc. Chem. Res., 42, 641-648, 2009.


The affordable accuracy depends on molecular size and particularly on the total number of atoms: for orientation, ethanol has 9 atoms, aspirin 21 atoms, morphine 40 atoms, sildenafil 63 atoms, paclitaxel 113 atoms, insulin nearly 800 atoms, and quaternary hemoglobin almost 12000 atoms. Currently, molecules with up to 10 atoms can be very accurately studied by coupled cluster (CC) theory, 100 atoms with second-order Møller-Plesset perturbation theory (MP2), 1000 atoms with density functional theory (DFT), and beyond that number with semiempirical quantum chemistry and force-field methods. The overwhelming majority of present-day calculations in the 100-atom range use DFT.


Dealing with nanomaterials is a challenge for both, experiments and theory.

Hence, our goal was to combine both approaches to elucidate and predict their physical and chemical properties, ranging from optical properties, such as photoluminescence (chapter 7), . growth mechanism of nanomaterials (chapter 8), simple and complex metal oxides. (chapter 9), as well as nanocatalysis (chapter 10)

Breakthroughs will continue to emerge when applications of visualization methods extend into systems of thousands of atoms and cells, and when the pertinent concepts are generalized with the help of “simple, but not too simple” theories.

Computations should be considered as tools, keeping in mind that largescale computations without a “final” theoretical condensate (or better yet, a “simple equation”) are like large-scale experiments which produce numerous results that do not boil down to a meaningful finding.

In the end, we may or may not find that the whole is greater than the sum of its parts, and learn why nature has designed unique, classical functions in the quantum world of atoms and molecules.

From both experimental and theoretical studies, the ultimate goal is to provide an understanding of the function from knowledge of structure and dynamics on different length and time scales. It would be naive to ignore the evolution of dynamics on these different scales, beginning with atomic motions, just as ignoring the “big bang” would be misleading for an understanding of the evolution of planets in the cosmic network.

Raphael’s School of Athens. Exactly five centuries ago, between 1510 and 1511, Raphael captured in his painting the intellectual discourse of philosophers most probably thinking about the fundamentals of nature.

Natural philosophy, the fundamental science of today, remarkably emphasized, in the quest for knowledge, dialogue of civilizations, regardless of origin, faith or gender.

Shown in the painting, among others, are Plato, Aristotle, Ptolemy, Hypatia of Alexandria, Pythagoras, Alexander the Great, Saladin, and Euclid (Archimedes).

Note also the beauty of the place where the discourse was held, especially when compared with many of the present-day university buildings.

The Next Decade of Nanoscience and Nanotechnology

D. Bonnell, ACS Nano, 4, 6293 (2010)

This review reveals that the past decade has indeed seen transformative changes in the scientific landscape due to nanoscience and nanotechnology advances. A reminder of the changes would include the following:

● Although plasmons have been around for decades, the ability to exploit them in nanostructures led to the burgeoning new field of plasmonics, which did not exist 10 years ago and is producing new technologies.

● After many years of new physics and innovative device configurations arising from the study of fullerenes and nanotubes, graphene exploded onto the scene and may enable the realization of the carbon-based systems. That the Nobel Prize in Physics recognized this new field this year is an indication of the significance of these advances (see Dresselhaus, M. S.; Araú jo, P. T. The 2010 Nobel Prize in Physics for Graphene: Some Perspectives. ACS Nano, 4, 6297 (2010))

● Combinations of near-field optical physics and biochemistry are producing gene sequencing solutions that may soon meet the $1000/genome challenge and are enabling single-molecule tracking in dynamic systems such as motor proteins.

● New families of hybrid materials/structures are being discovered that exhibit multifunctional behavior, such as multiferroics, spin torque systems, plasma-induced electronics, and bio-optoelectronics. (see Weiss, P. S. Combining Function. ACS Nano 2010, 4, 3535 (2010).

● Though local probes of atomic- and molecular-scale structure have been around for more than a decade, the last 10 years have seen dramatic extensions to imaging complexity and function at atomic levels. Advances such as nano nuclear magnetic resonance, spin excitation, and dielectric function portend a generational leap in our ability to understand nanoscale phenomena. Note that the 2010 Kavli Prize in Nanoscience acknowledged this.

● The new field of nanotoxicology and environmental health and safety is developing the scientific underpinning and social framework for responsible nanotechnology development (see ACS Nano’s Virtual Issue on nanotoxicology, http://pubs.acs.org/page/ancac3/vi/1)

Multiscale modelling can be defined as the concurrent study of the different time and length scales relevant for complex chemical, physical or biological processes. While this concept is already used in many areas of physics and material science (e.g. engineering, fluids, and aerodynamics), its realization in physical chemistry and chemical physics is still relatively new.

Within these disciplines, a multiscale approach connects the established fields of quantum chemistry, classical molecular dynamics, computational materials science, and bioinformatics. The importance of such an integral view for important processes such as photosynthesis, protein folding, DNA replication, catalysis, etc. is evident.

With the theoretical models in the above-mentioned fields reaching maturity, complex simulation workflows are emerging that link quantum mechanical(QM), molecular mechanics (MM), coarse-grained (CG), and continuum descriptions. The focus is thereby changed from the improvement of individual components of a workflow, calculations at a single length and/or time scale, to the improvement of the complete model and the transfer of information between the levels.

Feeding the larger length scale simulations with ab initio parameters from lower length scales requires a thorough matching of the physics in the two models and efficient implementation of the entire workflow.

As multiscale modelling developments are primarily discussed in the literature of the parent fields, cross-fertilization between the different fields is still limited. This themed issue, collecting ideas on multiscale modelling across the broad field of physical chemistry and chemical physics, therefore aims to enhance the interdisciplinary exchange of ideas.

The future is hard to predict. Yet, it is almost certain that in the coming decades new multiscale modelling methods, comprising quantum chemistry, classical MD, static and dynamic coarse graining, multi-level and hybrid simulations in all their forms will continue to be developed, allowing researchers in the field of physical chemistry and chemical physics to access ever more complex systems on larger length and time scales, without loosing essential microscopic features.

Multiscale modellingL. Visscher, P. Bolhuis, and F. M. Bickelhaupt, Phys. Chem. Chem. Phys., 2011, 13, 10399.

Read

Nano-Age. How Nanotechnology Changes our Future.

By Mario Pagliaro. Wiley-VCH, Weinheim 2010.

This book attempts to answer such questions. It is a perspective about the impact (past, present, and possibly future) of nanotechnology in society

Read

The long view of nanotechnology development: the National Nanotechnology Initiative at 10 years

M. C. Roco, J Nanopart Res (2011) 13:427–445

Read

Nano-Age. How Nanotechnology Changes our Future.

By Mario Pagliaro. Wiley-VCH, Weinheim 2010.

This book attempts to answer such questions. It is a perspective about the impact (past, present, and possibly future) of nanotechnology in society

Read

From Ideas to Innovation: Nanochemistry as a Case Study

G. A. Ozin and L. Cademartiri, Small 2010, DOI: 10.1002/smll.201001097

Read

Quantum well structures in thin metal films: simple model physics in reality?

M Milun, P Pervan and D P WoodruffRep. Prog. Phys. 65 (2002) 99–141

Read

Van Hove Singularities as a Result of Quantum Confinement: TheOrigin of Intriguing Physical Properties in Pb Thin Films

Y. J. Sun, S. Souma, W.J. Li, T. Sato, X. G. Zhu, G. Wang, X. Chen, X. C. Ma, Q. K. Xue, J. F. Jia, T. Takahashi, and T. Sakurai

Nano Res. 2010, 3(11): 800–806

Read

The devil is in the details (or the surface): impact of surface structure and surface energetics on understanding the behavior of nanomaterials in theEnvironment.

I. A. Mudunkotuwa and V. H. Grassian, J. Environ. Monit., 2011, 13, 1135

Read

Nanosensors: Does Crystal Shape Matter?

A. Gurlo, Small 2010, 6, No. 19, 2077–2079

Read

Nanotechnology Regulation: A Study in Claims Making

T.F. Malloy, ACS Nano, 5, 5-12 (2011)

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