EIGHTEENTH AUSTIN SYMPOSIUM ON MOLECULAR STRUCTURE

TABLE OF CONTENTS

March 6 - 8, 2000

Pages

Schedule i-xvi

Abstracts: Monday Sessions 1 - 11

Monday Poster Session 1 12 - 31

Tuesday Sessions 32 - 45

Wednesday Sessions 46-54

Wednesday Poster Session II 55 - 72

Supplementary Abstracts 73 - 98

Index of Authors 99 -105

We greatly appreciate support from:The University of Texas College of Natural SciencesThe University of Texas Department of Chemistry

UB/TIB Hannover 89121 306 828

MONDAY MORNING SESSIONMarch 6, 2000

Chair: Heinz Oberhammer

University of Ulm, Ulm, Germany

8:30 James E. Boggs: Introductory Remarks

8:40 MM1 Jean DemaisonUniversite de Lille, Villeneuve d'Ascq, France"How Accurately Can the Structure of a Molecule be Determined"

9:30 MM2 Peter Groner and Robin D. WarrenUniversity of Missouri-Kansas City, Kansas City, Missouri, U.S.A.

"Pseudo-re Structures from Experimental Rotational Constants and Ab InitioVibration-Rotation Constants"

9:50 MM3 Sarah L. Hinchley. Carole A. Morrison, Blair F. Johnston, Heather E.Robertson, and David W. H. RankinUniversity of Edinburgh, Edinburgh, Scotland, United Kingdom

"Small Molecules are Not Enough"

10:10 Break

10:40 MM4 Sudarko. T. M. Hughes, and Ellak I. von Nagy-FelsobukiUniversity of Newcastle, Callaghan, Australia

"Ro-vibrational Transition Energies and Absorption Intensities of the 1A3 Statesof H2O, He2O2+, and He2S"

11:00 MM5 Keiichi Tanakaa>b, Asao Mizoguchi3, and Kensuke Harada3

aInstitute for Molecular Science, Okazaki, Japan^Kyushu University, Hakozaki Fukuoka, Japan

"Millimeter Wave Spectroscopy Combined with Pulsed-Jet Expansion Techniquefor the Detection of the van der Waals Mode Transitions of Molecular Clusters"

11:20 MM6 Alan D. Richardsona, Kenneth Hedbergar and George Lucierb

aOregon State University, Corvallis, Oregon, U.S.A.^University of California, Berkeley, California, U.S.A.

"Structures of the Third Row Transition-Metal Hexafluorides Revisited"

11:40 MM7 Yaoming Xie and Henry F. Schaefer. IllUniversity ot Georgia, Athens, Georgia, U.S.A.

'The Puzzling Infrared Spectra of the Nitric Oxide Dimer Radical Cation: ASystematic Application of Brueckner Methods"

12:00 LunchMONDAY AFTERNOON SESSION

March 6, 2000

Chair: Attila G. CsaszarEotvos University, Budapest, Hungary

1:30 MAI PekkaPyykkoUniversity of Helsinki, Helsinki, Finland

"New Simple Inorganic Species"

2:20 MA2 V. G. SolomonikIvanovo State University of Science and Technology, Ivanovo, Russia

"Structure and Spectra Determination for High Temperature Molecular SpeciesContianing d and f Metals: Key Role of Ab Initio Quantum MechanicalCalculations"

2:40 MA3 L. L Lohr and S. M BlinderUniversity of Michigan, Ann Arbor, Michigan, U.S.A.

"New Partitionings of the Rotational and Vibrational Motions of Molecules"

3:00 MA4 Vladimir S. Mastryukov, C. Ruan, and Manfred FinkUniversity of Texas, Austin, Texas, U.S.A.

"Electron Diffraction Studies of Metal Phthalocyanines: NiPc and CuPc"

3:20 - 5:00 Poster Session IPosters 1 - 20

POSTER SESSION IMonday, March 6, 2000

3:20- 5 :00 PM

PI D. Thastum Bach3, F. Hegelunda, J. A. Beukesb, F. M. Nicolaisenb, and M. H.Palmerc

fAarhus University, Aarhus, DenmarkUniversity of Copenhagen, Copenhagen, Denmark

cUniversity of Edinburgh, Edinburgh, Scotland, United Kingdom'The High Resolution Infrared Spectrum of 1,2,4-Triazine Vapor between 550 and1700 cm-1"

P2 Nikolai Balabanov and James E. BoggsUniversity of Texas, Austin, Texas, U.S.A.

"Molecular and Electronic Structure of Transition Metal Trihydrides MH3 (M = Cr,Mo, W; Cu, Ag, Au)"

P3 Keith Ballentine and John F. StantonUniversity of Texas, Austin, Texas, U.S.A.

"Surprisingly Facile Rearrangement of Substituted Vinylidenes"

P4 Suleman Bahceci and Isaac B. BersukerUniversity of Texas, Austin, Texas, U.S.A.

"Improved Electron-Conformational Method of Pharmacophore Identifican andBioactivity Prediction: Application to ACE and HIV-1 Integrase Inhibitors"

P5 Jiirgen Vogt. Natalja Vogt. and Wolfgang HutterUniversitat Ulm, Ulm, Germany

"New Featurs of the MOGADOC Database"

P6 F. Blockhuys. H. E. Robertson, and D. W. H. RankinUniversity of Edinburgh, Edingurgh, Scotland, United Kingdom

"Gas Phase Structures of 1,3 X482,2,4-Benzodithiadiazine and its 4,5,6,7-TetrafluroDerivative"

P7 P. Boyer, A. Akoubri, V. Ledauphin, and G. VergotenUniversite des Sciences et Technologies de Lille, Lille, France

"Molecular Electromagnetic Communications and Molecular Recognition"

P8 Amy Campbell3, Sarah Nagelb, Willard Collierb. and Svein Saebob

^University of North Alabama, Florence, Alabama, U.S.A.bMississippi State University, Mississippi State, Mississippi, U.S.A.

"Evaluation of the Aromatic Character of some [N]-Pericyclynes and [N]-Oxocyclynes using Ab Initio NMR Calculations"

P9 Marwan DakkouriUniversitat Ulm, Ulm, Germany'The Gas-Phase Structure of 1,1-Dicyanocyclopentane as Determined by ElectronDiffraction and Ab Initio Computation"

P10 Kurt W. Sattelmeyer and John F. StantonUniversity of Texas, Austin, Texas, U. S. A."Performance of Triples-Corrected Equation of Motion Coupled Cluster Methodsfor Potential Eneergy Functions of Excited States"

Pll A. V. Marenich and V. G. SolomonikIvanovo State University of Chemical Sciences and Technology, Ivanovo, Russia"An Ab Initio Study of the Structure and Isomerism of M2XO4 Molecules (with M= Li, Na, K; X = Cr, Mo, W)"

P12 Toru Egawa and Shigehiro KonakaHokkaido University, Sapporo, Japan"Electron Diffraction Study of 2-Butanimine, an Unstable Imine"

P13 L. L. Griffin. H.-Y. Zhu, D. J. Klein, A. Rubio, N. N. March, T. G. Schmalz,W. A. Seitz, and T. P. ZivkovicTexas A&M University at Galveston, Galveston, Texas, U.S.A."Carborazines and Their HOMO-LUMO Gaps"

P14 Chona S. Guiang and Robert E. WyattUniversity of Texas, Austin, Texas, U.S.A."Quantum Control of I2 Wavepacket Localization in Solid Argon Matrix"

P15 Kolbjorn Hagena. Alan D. Richardsonb. Ouang Shenc . and MaritTraetteberga

^Norwegian University of Science and Technology, Trondheim, Norway"Oregon State University, Corvallis, Oregon, U.S.A.cColgate University, Hamilton, New York, U.S.A.

"Structure and Conformation of Styrene and Bromo-Substituted StyrenesDetermined by Gas-Phase Electron Diffraction and Ab Initio Molecular OrbitalCalculations"

P16 D. Hnyka, V. Vseteckab. L. Drozc, M. A. Foxc, H. MacBridec, and K. Wadec

^Academy of Sciences of the Czech Republic, Rez, Czech RepublicCharles Univeresity, Prague, Czech Republic

cUniversity of Durham, Durham, United Kingdom"Transmission of Electronic Effects by Icosahedral 1,2-closo- C2B10H12 and 1,12-closo- C2B10H12 as Studied by Dipole Moments. A Direct Evidence of ChargeDistribution within l,2-c/oso-C2B10H12"

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P17 D. Hnyka. K. B. Borisenkob, S. Samdalb, and Otto Exner1

^Academy of Sciences of the Czech Republic, Rez, Czech RepublicUniveresity of Oslo, Blindern, Oslo, Norway

"Structure and Conformation of Methyl 2-Methyl Benzoate: Steric Effect of aSmall ortfio-Substituent"

P18 D. J. W i l s o n . Sudarko, J. M. Hughes, and E. I. von Nagy-Felsobuki

University of Newcastle, Callaghan, Australia

"Ab Initio Ro-vibrational Spectra of the 2Aa States of He2C3+"

P19 B. F. Johnston. C. A. Morrison, D. W. H. Rankin, and H. E. RobertsonUniversity of Edinburgh, Edinburgh, Scotland, United Kingdom"Two Tin Compounds - A Gas-Phase Electron Diffraction Study of Me3SnC4F9

and Me3SnOC(O)C2F5"

P20 James A. Kelly3, HI, Robert K. Bohna. and Nancy S. Trueb

^University of Connecticut, Storrs, Connecticut, U.S.A.University of California, Davis, California, U.S.A.

"Rotational Spectral Anomolies and Conformations of p-n-Propyl Benzaldehyde"

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TUESDAY MORNING SESSIONMarch 7, 2000

Chair: Larence L. LohrUniversity of Michigan, Ann Arbbr, Michigan, U.S.A.

8:30 TM1 Takashi NagataUniversity of Tokyo, Tokyo, Japan

"Structure and Dynamics of Negatively-Charged Molecular Clusters: Coexistenceof Electronic Isomers and Floppiness of their Shapes"

9:20 TM2 Robert L. Kuczkowski. R. A. Peebles, and S. A. PeeblesUniversity of Michigan, Ann Arbor, Michigan, U.S.A.

"Weakly Bonded Trimers"

9:40 TM3 N. H. Martin. N. W. Allen, III, J. D. Brown, S. T. Ingrassia, and E. K.MingaUniversity of North Carolina at Wilmington, U.S.A.

"Predicting NMR Deshielding by Alkenes Based on Ab Initio GIAOCalculations"

10:00 Break

10:30 TM4 Anne-Marie Kelterer8. A. D. French**, and G. P. Johnson^aTechnische Universitat Graz, Graz, Austria^Southern Regional Research Center, New Orleans, Louisiana, U.S.A."Conformational Analysis of a,a-Trehalose by a QM/MM Hybrid Method inComparison with Crystal Structures"

10:50 TM5 J. Laane. K. Morris, Z. Arp, S. Sakurai, E. Bondoc, and N. MeinanderTexas A&M University, College Station, Texas, U.S.A.

"Vibrational Potential Energy Surfaces for the Ring-Puckering and Ring-FlappingVibrations of Phthalan, 1,3-Benzodioxole, Coumaran, and Indan in Their So andSa (TI, 7C*) Electronic States"

11:10 TM6 RPuky, L. Fusti-Molnar, and J. BakerUniversity of Arkansas, Fayetteville, Arkansas, U.S.A.

"Classical Molecular Dynamics in General Curvilinear Internal Coordinates"

11:30 TM7 Jerzy LeszczynskiJackson State University, Jackson, Mississippi, U.S.A.

"Shellvation: A New Phenomenon Revealed by Computational Studies"

11:50 Lunch

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TUESDAY AFTERNOON SESSIONMarch 7, 2000

Chair: Kenneth HedbergOregon State University, Corvallis, Oregon, U.S.A.

1:30 TA1 C. Henrik Ottosson, Heather Fogarty, Robert Zink, and Josef MichlUniversity of Colorado, Boulder, Colorado, U.S.A."New Surprises in an Old Field: Conformations and Electronic Structure ofSaturated Chains"

2:20 TA2 Michael Rameka and Sanja Tomicb

aTechnische Universitat Graz, A-8010 Graz, AustriabInstitut Ruder Boskovic, Zagreb, Croatia'Theoretical Structure Investigations of 3-Indole Acetic Acid Derivatives"

2:40 TA3 Shigehiro Konaka. Takemasa Tsuji, Kaori Inoue, Hiroshi Takeuchi,and Toru EgawaHokkaido University, Sapporo, Japan

"Structures of Molecules Closely Related to Liquid Crystals"

3:00 Break

3:30 TA4 Colin J. Marsden. Nina Ismail, and Jean-Louis HeuillyUniversite Paul Sabatier, Toulouse, France

'The Structural Chemistry of Uranium: the Uranyl Ion and Related Systems"

3:50 TA5 John F. Stanton. T. Daniel Crawford, and Tamal C. SaehUniversity ot Texas at Austin, Austin, Texas"Success and Disaster in the Description of Radical Potential Energy Surfaces"

4:10 TA6 T. V. Timofeevaa. F. M. Dolgushina. and C. T. Burnsb

aNew Mexico Highlands University, Las Vegas, New Mexico, U.S.A.bLos Alamos National Laboratory, Los Alamos, New Mexico, U.S.A.

"Molecular Mechanics of Actinide Complexes. Statistical Analysis of MolecularStructure of Uranium and Thorium Complexes Found in Cambridge StructuralDatabase"

4:30 TA7 M. L. Ellzey. Tr.University of Texas at El Paso, El Paso, Texas, U.S.A.

"Symmetry-Generated Effective Orbital Hamiltonian Treatment of MolecularStructure"

6:15 Social Hour

7:00 Symposium BanquetDavid W. H. Rankin, "Structural Chemistry: A View from Outer Space"University of Edinburgh, Edinburgh, Scotland, United Kingdom

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WEDNESDAY MORNING SESSIONMarch 8, 2000

Chair: Isaac B. BersukerUniversity of Texas, Austin, Texas, U.S.A.

8:30 WM1 Paul v. R. SchleyerUniversity of Georgia, Athens, Georgia, U.S.A.

"Relationships between Structural and Other Criteria of Aromaticity"

9:20 WM2 Attila G. Csaszar*. Gyorgy Tarczaya, Oleg Polyanskyb and JonathanTennysonb

aEdtv6s University, Budapest, HungarybUniversity College London, London, United Kingdom

"Ab Initio Spectroscopy of H2S"

9:40 WM3 Oktay SinanogluYlidiz Teknik Universitesi, Istanbul, Turkey and Yale University, New Haven,Connecticut, U.S.A.

"From Chemical Structures Directly to Quantum Electronic Stability, Reactivity.Pictorial Rules, no Computation, with Examples, including Electron-DeficientCompounds and Ions"

10:00 Break

10:30 WM4 Ann Schmiedekampa and K. P. R. Nairb

aPenn State University, Abington College, Abington, Pennsylvania, U.S.A.bCochin University of Science and Technology, Cochin, India

"Calculations of Methyl Fluorosulfonate and Methyl Chlorosulfonate: AComparison between Theory and Experiment"

10:50 WM5 To be announced.

11:10 WM6 Douglas J. Klein and L. BytautasTexas A&M University at Galveston, Galveston, Texas, U.S.A.

"All Acyclic Hydrocarbons: Formula Periodic Table for Isomer Classes; IsomerEnumeration and Asymptotics; Means of Local Graph Invariants; MeanMolecular-Properties via Cluster Expansion; and Property Overlap Plots"

11:30 WM7 H. Koizumi3 .1. B. Bersukerb, J. E. Boggsb, and V. Z. Polinger0

aHimeji Institute of Technology, Hyogo, JapanbUniversity of Texas, Austin, Texas, U.S.A.cUniversity of Washington, Seattle, Washington, U.S.A.

"Conical Intersections and Tunneling Splitting in Jahn-Teller Systems"

11:50 Lunch

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WEDNESDAY AFTERNOON SESSION

March 8, 2000

Chair: Carole MorrisonUniversity of Edinburgh, Edinburgh, Scotland, United Kingdom

1:30 WAI Heinz OberhammerUniversitat Tubingen, Tubingen, Germany

"The N-O Single Bond in Covalent Nitrates and Nitrites"

2:20 WA2 K. P. R. NairCochin University of Science and Technology, Cochin, Kerala, India

"Microwave and Diode Laser Spectroscopy of Some Diatomic Moleucles"

2:40 4:30 Poster Session IIPosters 21 -38

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POSTER SESSION IIMonday, March 6, 2000

3:20- 5 :00 PM

P21 UHnyk3 and S. Samdalb

fAcademy of Sciences of the Czech Republic, Rez, Czech Republic"Univeresity of Oslo, Blindern, Oslo, Norway

"Molecular Structure of l-Thia-c/oso-Decaborane(9) in the Gas Phase asDetermined by Electron Diffraction and Theoretical Calculations of VariousQuantities"

P22 O. Yu. Marochko and V. G. Solomonik ,

Ivanovo State University of Chemical Sciences and Technology, Ivanovo, Russia

"Are Group 3 Metal Trihalide Molecules Planar, Nonplanar, or Quasi-Planar?MHal3 ( M = Sc, Y, La, Lu; Hal = F, Cl, Br, I) Floppiness and its SpectroscopicManifestation: Ab Iniio CISD+Q Study"

P23 Vladimir S. MastryukovUniversity of Texas, Austin, Texas, U.S.A.

"Pyramidality of sp2 Carbon Atoms as Studied by Ab Initio Calculations UsingEthylene as a Model"

P24 R. J. Mawhortei*. P. T. Brainb, B. A. Smartb, C. A. Morrisonb, and D. W. H.Rankinb

fPomona College, Claremont, California, U.S.A.University of Edinburgh, Edinburgh, Scotland, United Kingdom

"An All-Mode Vibrational Analysis of the Sodium Chloride Dimer"

P25 C. A. Morrison. H. E. Robertson, and D. W. H. RankinUniversity of Edinburgh, Edinburgh, Scotland, United Kingdom

"Recent Resuts from the Edinburgh Electron Diffraction Group: The Structures ofSome Crowded Silanes and Ferrocene Derivatives"

P26 Tamal C. Saeh and John F. StantonUniversity of Texas, Austin, Texas, U. S. A.

"Improved Coupled-Cluster Methods for Doublet Radicals"

P27 T. Pefia Ruiza. M. Fernandez Gomez3, J. J. Lopez Gonzalez3, A. Navarroa,and A. Koziolb

jKJniversidad de Jaen, Jaen, SpainUniwersytet Marii Curie-Sklodowskiej, Lublin, Poland

"Structural and Vibrational Analysis of Precursors of Biomedical Interest. TheCase of 5-Chloro-l-Indanone"

P28 B. K. Novosadov3, O. Yu. Nikitinb, A. W. Niukkanenc, and V. I.Perevoztchikov^

^Moscow State University, Moscow, RussiaMoscow State Textile Academy, Moscow, Russia

^Russian Academy of Science, Moscow, RussiaMoscow State Open University, Moscow, Russia

"Combination of the Modified Atom and ^-Factorization Methods to Create NewGeneration Software for Molecular Structure Calculations in a Basis ofExponential Functions"

P29 R. C Dudek. S. Ryu, R. M. Stratt, and Peter M. WeberBrown University, Providence, Rhode Island, U.S.A.

"Examining Molecular Excited States Using Ultrafast Pump-Probe ElectronDiffraction"

P30 Victor P. Spiridonova, Natal j a Vogtb. and Turgen Vogtb

fMoscow State University, Moscow, RussiabUniversitat Ulm, Ulm, Germany"Equilibrium Molecular Structues from Different Methods"

P31 Sudarko, J. M. Hughes, and E. I. von Nagy-FelsobukiUniversity of Newcastle, Callaghan, Australia"Ab Initio Ro-vibrational Spectra of the ^ States of He2C

2+ and He2Si2+"

P32 Keiichi Tanaka and Takehiko TanakaKyushu University, Hakozaki Fukuoka, Japan"Time-Resolved Diode Laser Spectroscopy of Jet-Cooled Fe(CO)x RadicalsProduced by UV Laser Photolysis of Fe(CO) 5"

P33 Mouhsine Tazi, Philippe Lagant, and Gerard VergotenUniversite des Sciences et Technologies de Lille, Lille, France"The Free Base Porphin and Metalloporphyrins Normal Modes as Obtained fromDFT Methods: Checking for the Scaled Force Field Using Resonance RamanIntensities for the Totally Symmetric Modes"

P34 J. Vazquez Ouesada3, J. Demaisonb, James E. Boggsc, and H. D. Rudolphd

fUniversidad de Jaen, Jaen, SpainUniversite de Lille I, Villeneuve d'Ascq, France

^University of Texas, Austin, U.S.A.University of Ulm, Ulm, Germany

"Structure and Force Field of Furazane"

P35 M.L.Ellzey,Jr.University of Texas at El Paso, El Paso, Texas, U.S.A.

"Applications of the Symmetry-Generation Theorem"

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P36 Isaac B. Bersuker, Siileyman Bahceci, and Jun LuoUniversity of Texas, Austin, Texas, U.S.A.

"Identificaion of the Pharmacophore and the Anti-Tumor Activity of PlatinumCompounds by the Electron-Conformational Method"

P37 Amanda Willis3, Robert K. Bohn3. and Joseph Kneec

3Mt. Holyoke College, South Hadley, Maine, U.S.A."University of Connecticut, Storrs, Connecticut, U.S.A.cWesleyan University, Middletown, Connecticut, U.S.A.

'The Conformation and Torsional Potential Function of Cyclopropyl Benzene"

P38 A. V. Belyakov3. A. Haalandb, D. J. Shorokhovb, and H. V. Voldenb

3St. Petersburg Technological Institute, St. Petersburg, RussiabUniversity of Oslo, Blindern, Oslo, Norway"Gas-Phase Electron Diffraction Study of Trimethylphosphite, P(OMe)3, Supple-mented by Ab Initio Calculations of Geometry and Force Constants"

SUPPLEMENTARY ABSTRACTS

51 M. Alcolea Palafox3, P. C. Gomez3, and L. F. Paciosb

fUniversidad Complutense Madrid, Madrid, SpainbUniversidad Autonoma de Puebla, Puebla, Mexico

"Structural Relations in the Amine Group of Aniline Derivatives with ortho-, meta-and para-Substituents"

52 M. Alcolea Palafox3, A. Rangel-Huertab, and F. J. Melendezb

fUniversidad Complutense Madrid, Madrid, SpainUniversidad Politecnica de Madrid, Madrid, Spain

"Ab Initio Study of Geometrical Structures of SiH3-XHn (X = Be, Mg, B, Al, N, Pand S) Silanes"

53 N. V. Anikeeva, G. M. Kuramshina, A. G. Yagola, and Yu. A. PentinMoscow State University, Moscow, Russia

"Optimizing Calculated n-Butane Conformer Force Fields by Using ExperimentalData within the Regularization Procedure"

54 Karissa G. Atticks and Robert K. Bohn

University of Connecticut, Storrs, Connecticut, U.S.A.

"Microwave Spectrum of 1-Hexyne (Butyl Acetylene)"

55 D. E. Autrey and J. LaaneTexas A&M University, College Station, Texas, U.S.A.

'Tar-Infrared, Raman, and Combination Band Spectra and Ring-Twisting PotentialEnergy Function of 1,3-Cyclohexadiene"

56 D. E. Autrey, A. del Rosario, and J. Laane

Texas A&M University, College Station, Texas, U.S.A.

"Far-Infrared Spectrum and Ab Initio Calculations for Vinylene Carbonate"

57 E. G. Atavin3 , M. I. Frolovaa, L. V. Khristenkob, B. V. Lokshinc, S.Gundersene, S. Samdale, L. V. Vilkovb, and E. N. Suslovad

^University of Omsk, Omsk, RussiaUniversity of Moscow, Russia

^Institute of Organic Chemistry, Moscow, Russia"Institute of Organic Chemistry, Irkutsk, RussiaeUniversity of Oslo, Oslo, Norway

"Molecular Structure of l,l-Dimethyl-3-thia-l-silacyclohexane from a Joint ElectronDiffraction, Vibrational Spectroscopic and Ab Initio Molecular Orbital Study"

X l l l

58 Victor J. BaranovVernadsky Institute, Russian Academy of Science, Moscow, Russia"Excited States Structure and Vibronic Spectra of Stilbene, Styrene, and theirMethyl- and Deutero-Substituted Derivatives"

59 M. A. Fernandez Oliva, N. Iza, M. Alcolea Palafox, and M. GilUniversidad Complutense Madrid, Madrid, Spain"Semiempirical and Ab Initio Study of Several Organophosphorus Pesticides"

510 A. I. Garcia, M. Alcolea Palafox, and M. GilUniversidad Complutense Madrid, Madrid, Spain'Theoretical Calculations of the Molecular Properties of Several HFCs"

511 P. C. Gomez3, M. Alcolea Palafox3, and L. F. Paciosb

fUniversidad Complutense Madrid, Madrid, SpainUniversidad Politecnica de Madrid, Madrid, Spain

"Inverted Forms of SiXnH3.nLi and SiXnH3.nNa Coumpounds"

512 A. R. Gopar Perdomo, M. Gil, N. Iza, and M. Alcolea PalafoxUniversidad Complutense Madrid, Madrid, Spain"Nucleic Base Pairs of Guanine and Cytosine: A Semiempirical and Ab InitioStudy in the Gas Phase and in a Water Cluster"

513 H. I. IsmailzadeNational Aviation Academy, Baku, Azerbaijan"Rotational Spectrum of Poorly-Connected Gas Phase Complexes: I(H20)2"

514 L. S. Khaikin3 ,0 . E. Grikina3, V. I. Perevoztchikovb. and S. Samdalc

fMoscow State University, Moscow, RussiaMoscow State Open University, Moscow, Russia

cUniversity of Oslo, Blindern, Oslo, Norway.'The Use of Quantum-Chemical and Spectral Data for N,N-Dimethylnitrosamine inElectron Diffraction Analysis"

515 L. S. Khaikin3, O. E. Grikina3, V. A. Sipachev3, A. A. Granovsky3, V. S.Nikitin3, A. V. Belyakovb. and E. T. Bogoradovskiib

^Moscow State University, Moscow, RussiaTechnological University, St. Petersburg, Russia

"Structure and Force Field of Bis(trimethylstannyl)acetylene: Accordance betweenAb Initio, Vibrational Spectrosocpy, and Electron Diffraction Data"

XXV

516 Leonid S. Khaikin?, Olga E. Grikinaa, and Marit Traettebergb

fMoscow State University, Moscow, RussiaUniversity of Trondheim, Trondheim, Norway

"Theoretical Investigation of Structure and Spectra of Acetylene Derivatives ofSilicon. Transferability of Scale Factors for Ab Initio Force Fields"

517 L. S. Khaikin3, O. E. Grikina3, E. A. Zhilinskayab, and B. I. Zhilinskiib

fMoscow State University, Moscow, RussiaUniversite du Littoral, Dunkerque, France

'Theoretical Study of Structure and Internal Rotation of Dimethylaminodi-clorophosphine. Analysis of the Vibratioanl Spectra with the Use of ScalingQuantum-Chemical Force Field"

518 L. S. Khaikin3 ,0. E. Grikina3, E. A. Zhilinskayab, and B. I. Zhilinskiib

fMoscow State University, Moscow, RussiabUniversite du Littoral, Dunkerque, France'Theoretical Study of 2-Chloro-l,3-dimethyl-l,3,2-benzodiazaphospholene.Equilibrium Structure and Prediction of Vibrational Frequencies with the Use ofScale Factors for Quantum-Chemical Force Field"

519 L. S. Khaikin3 ,0. E. Grikina3, E. A. Zhilinskayab, and B. I. Zhilinskiib

fMoscow State University, Moscow, RussiaUniversite du Littoral, Dunkerque, France

"Theoretical Study of 1,3,2-Dioxaphospholene Derivatives: Structure, Deformationof Unsaturated Five-membered Heterocycle, and Vibrational Spectra"

520 I. V. Kochikov, Yu. I. Tarasov, G. M. Kuramshina, V. P. Spridonov, A. G.Yagola, and Yu. A. PentinMoscow State University, Moscow, Russia"New Stable Numerical Procedures for Solving a Generalized Inverse StructuralProblem within the Anharmonic Approach"

521 S.-N. Lee and T. LaaneTexas A&M University, College Station, Texas, U.S.A."Electronic Absorption Spectra and Carbonyl Wagging Potential Energy Functionsof Cyclic Ketones"

522 F. J. Melendez3, A. Rangel-Huerta3, and M. Alcolea Palafoxb

^Universidad Autonoma de Puebla, Puebla, MexicoUniversidad Complutense Madrid, Madrid, Spain

"Semiempirical Study of the Pharmocologically Active Structures of Various LocalAnaesthetics of the Procaine Type"

XV

523 I. Merkea, K. Sarkab'c, J. Demaisonb. L. Margulesb, N. Heinekingd, H.Biirgere, and H. Rulande

fRWTH Aachen, Aachen, GermanyUniversite de Lille I, Villeneuve d'Ascq, France

^Comenius University, Bratislava, SlovakiaHumboldt University, Berlin, Germany

eUniversitat-GH Wuppertal, Wuppertal, Germany

"Centrifugal Distortion Analysis of a Quasi-Spherical Molecule. Determination ofSix Quartic Centrifugal Distortion Constants"

524 V. P. Novikov3, I. F. Shishkov3, L. V. Khristenko3, L. V. Vilkov3, M,Dakkourib. and R. G. Kostyanovskiic

fMoscow State University, Moscow, RussiaUniversity of Ulm, Ulm, Germany

cInstitute of Chemical Physics, Moscow, Russia"Conformations of Methoxymethylazeridine and Tris(azeridino)methane as a Testfor the Anomeric Effect"

525 I.YaOgurtsovState University of Moldova, Chisinau, Moldova"Pure Rotatonal Absorption and Raman Spectra of the VF3 and MnF3 Molecues"

526 M. I. Shilina, G. M. Kuramshina, V. V. Smirnov, and Yu. A. PentinMoscow State University, Moscow, Russia

"Structure and Vibrational Spectra of 1-Nitropropane Rotational Isomers:Theoretical and Experimental Studies"

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