GAS PHASE STRUCTURE AND STABILITY OF COMPLEX FORMED BY H2O, NH3, H2S AND THEIR METHYL DERIVATIVES WITH THE CATION CO2+

Ab initio molecular orbital calculations at the Hartree-Fock-Self Consistent Field (HF-SCF) have been performed in order to determine the structure and gas phase energies of complex formed by the Lewis bases of H2O, NH3, H2S and their methyl derivatives with the cation Co2+. The relative basicities of the base studied depend on both the substituent. The gas-phase interaction energies computed by the SCF method including electron correlation Møller-Plesset 2 (MP2) dan Configuration Iteration (CI) were comparable in accuracy. The binding energies computed by these two methods reach the targeted chemical accuracy. Keywords: ab initio calculation, cobalt complex, structure stability

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Gas-Phase Tautomerism in the Triazoles and Tetrazoles: A Study by Photoelectron Spectroscopy and ab Initio Molecular Orbital Calculations

Zeitschrift für Naturforschung A ◽

10.1515/zna-1981-1121 ◽

1981 ◽

Vol 36 (11) ◽

pp. 1246-1252 ◽

Cited By ~ 45

Author(s):

Michael H. Palmer ◽

Isobel Simpson ◽

J. Ross Wheeler

Keyword(s):

Ab Initio ◽

Gas Phase ◽

Molecular Orbital ◽

Photoelectron Spectroscopy ◽

Relative Stability ◽

Photoelectron Spectra ◽

Equilibrium Geometry ◽

Molecular Orbital Calculations ◽

Methyl Derivatives

The photoelectron spectra of the tautomeric 1,2,3,- and 1,2,4-triazole and 1,2,3,4-tetrazole systems have been compared with the corresponding N-methyl derivatives. The dominant tautomers in the gas phase have been identified as 2 H-1,2,3-triazole, 1 H-1,2,4-triazole and 2H-tetrazole.Full optimisation of the equilibrium geometry by ab initio molecular orbital methods leads to the same conclusions, for relative stability of the tautomers in each of the triazoles, but the calculations wrongly predict the tetrazole tautomerism.

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Ab initio study of the gas-phase structure and electronic properties of M–CH3 (M=Li, Na) and M–CCH (M=Li, Na, K): A combined post-Hartree–Fock and density functional theory study

The Journal of Chemical Physics ◽

10.1063/1.480671 ◽

2000 ◽

Vol 112 (3) ◽

pp. 1178-1191 ◽

Cited By ~ 21

Author(s):

G. Scalmani ◽

J. L. Brédas ◽

V. Barone

Keyword(s):

Density Functional Theory ◽

Ab Initio ◽

Gas Phase ◽

Phase Structure ◽

Density Functional ◽

Ab Initio Study ◽

Density Functional Theory Study ◽

Functional Theory ◽

Hartree Fock ◽

Gas Phase Structure

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Ab Initio Computation of Thermochemistry and Kinetics in the Oxidation of Gas Phase Silicon Species

MRS Proceedings ◽

10.1557/proc-282-493 ◽

1992 ◽

Vol 282 ◽

Author(s):

Michael R. Zachariah ◽

Wing Tsang

Keyword(s):

Ab Initio ◽

Gas Phase ◽

Energy Barrier ◽

Reaction Rate ◽

Rate Theory ◽

Molecular Orbital Calculations ◽

Activation Energy Barrier ◽

Ab Initio Computation ◽

Oxygen Donor ◽

Reaction Rate Theory

ABSTRACTAb initio molecular orbital calculations coupled to RRKM reaction rate theory have been conducted on some important reactions involved in the oxidation of silane in a high-temperature/high H2O environment. The results indicate thatH2O acts as an oxygen donor to SiH2 to form H3SiOH or SiH2O. Subsequent reactions involve the formation of (HSiOOH, H2Si(OH)2,:Si(OH)2 or SiO). In turn SiO polymerizes into planar rings, without an activation energy barrier. A list of calculated thermochemical data are also presented for a number of equilibrium species.

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