Ab initio Predictions of the Gas-Phase Acidities of Diazirine and Diazomethane

1995 ◽  
Vol 48 (2) ◽  
pp. 401 ◽  
Author(s):  
AJ Russell ◽  
AP Scott ◽  
L Radom
Keyword(s):  
Ab Initio ◽  
Gas Phase ◽  
Molecular Orbital ◽  
Calculated Result ◽  
Molecular Orbital Calculations ◽  
Experimental Values

Absolute gas-phase acidities of diazirine, diazomethane, dimethylamine, ethylamine and methylamine have been obtained with ab initio molecular orbital calculations at the G2 and G2(MP2) levels of theory. Values at the G2 and G2(MP2) levels are all within 1 kJ mol-1 of one another. The calculated gas-phase acidities for diazomethane, dimethylamine, ethylamine and methylamine (and other reference molecules considered) are all within 3 kJ mol-1 of experiment. For diazirine the calculated result, although consistent with experiment, would suggest an acidity towards the lower end of the range of possible experimental values.

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

1981 ◽  
Vol 36 (11) ◽  
pp. 1246-1252 ◽  
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.

Sign in / Sign up

Export Citation Format

Share Document