Charge localization by molecular orbital calculations. II. Formamide,thioformamide and N-methylated analogues

Ab initio molecular orbital calculations have been used to determine the degree of charge localization associated with the formation of radical cations on electron impact of formamide, thioformamide and their N-methyl and N, N-dimethyl analogues. The charge favours the nitrogen of formamides and the sulphur of thioformamides, but the degree of localization is calculated to be lower than in the radical cations of urea and thiourea.