Molecular orbital calculations of valency within the framework of a general non-singular transformation of the atomic orbital basis sets

Ab initio molecular orbital theory with the minimal STO-3G and split-valence 4-31G basis sets is used to obtain geometries of 18 anions:OH-, NH2-, HF2-, BH4-, BF4-, C22-, CN-, NCN2-, N3-, NO2-, NO3-, 0CCO2-, CO32-, HCOO-, CH3COO-, C2O42-, C4O42- and C(CN)3-. The theoretical results are compared with experimental results from the literature. The STO-3G basis set performs somewhat worse for anions than for neutral molecules. On the other hand, the 4-31G basis set gives good results and predicts bond lengths to within 0.02� for all the molecules considered. Limited information on bond angle predictions suggests that these are of comparable quality to those for neutral molecules. The tricyanomethanide ion is predicted to be planar.

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Handbook of gaussian basis sets: A compendium for ab-initio molecular orbital calculations. By Raymond Poirier, Roy Kari, and Imre Csizmadia. Elsevier science publishers B.V., Amsterdem, 1985

International Journal of Quantum Chemistry ◽

10.1002/qua.560320414 ◽

1987 ◽

Vol 32 (4) ◽

pp. 549-549

Author(s):

Hans Ågren

Keyword(s):

Ab Initio ◽

Molecular Orbital ◽

Basis Sets ◽

Molecular Orbital Calculations ◽

Gaussian Basis Sets

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Ab initio molecular orbital study of simple 1,3-dipolar reactions

Australian Journal of Chemistry ◽

10.1071/ch9760465 ◽

1976 ◽

Vol 29 (3) ◽

pp. 465 ◽

Cited By ~ 27

Author(s):

D Poppinger

Keyword(s):

Transition State ◽

Ab Initio ◽

Molecular Orbital ◽

Transition States ◽

Basis Sets ◽

Molecular Orbital Calculations ◽

Molecular Orbital Study ◽

Orbital Study ◽

Extended Basis ◽

Optimized Geometries

Ab initio molecular orbital calculations with minimal and extended basis sets have been carried out for the 1,3-dipolar addition of fulminic acid to acetylene, ethylene, ethynamine and propynenitrile. Optimized geometries are reported for the transition states HCNO+C2H2, HCNO+C2H4, HCNO+ C2HNH2, for the adducts isoxazole and 2-isoxazoline, and for nitrosocyclopropene as a possible intermediate. The calculations indicate that (a) these 1,3-dipolar reactions are synchronous processes, (b) the geometry of the transition state is insensitive to substitution and (c) of the isomeric substituted adducts, 5-aminoisoxazole and isoxazole-4-carbonitrile should be formed preferentially.

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Liquid Water through Density-Functional Molecular Dynamics: Plane-Wave vs Atomic-Orbital Basis Sets

Journal of Chemical Theory and Computation ◽

10.1021/acs.jctc.6b00271 ◽

2016 ◽

Vol 12 (8) ◽

pp. 3456-3462 ◽

Cited By ~ 18

Author(s):

Giacomo Miceli ◽

Jürg Hutter ◽

Alfredo Pasquarello

Keyword(s):

Molecular Dynamics ◽

Plane Wave ◽

Liquid Water ◽

Density Functional ◽

Atomic Orbital ◽

Basis Sets ◽

Orbital Basis

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The electronic absorption spectra of some N-sulfinylanilines. A molecular orbital treatment

Canadian Journal of Chemistry ◽

10.1139/v97-112 ◽

1997 ◽

Vol 75 (7) ◽

pp. 934-941 ◽

Cited By ~ 2

Author(s):

R. Abu-Eittah ◽

H. Moustafa ◽

A.M. Al-Omar

Keyword(s):

Absorption Spectra ◽

Molecular Orbital ◽

Electron Acceptor ◽

Electronic Absorption ◽

Electronic Absorption Spectra ◽

Basis Sets ◽

Theoretical Treatment ◽

Molecular Orbital Calculations ◽

Strong Electron ◽

Anti Conformer

The electronic absorption spectra of N-sulfinylaniline and some of its derivatives were investigated using different solvents. The spectral behavior of the molecules indicated their planarity and that the NSO group is a strong electron acceptor. All the observed bands correspond to delocalized π → π* transitions; n → π* transition were not observed as discrete bands. Ab initio molecular orbital calculations were performed using four different basis sets. The results showed that the NSO group is nonlinear, the molecules studied are planar, and the syn conformer is more stable than the anti conformer. Keywords: N-sulfinylanilines, spectra and theoretical treatment.

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