Calculations on the relative energies of complexes of silanes with ²π and ⁴πNO

Abstract

A theoretical study is presented of the relative enthalpies (calculated through heats of atomisation) of complexes of the silanes SiF4, SiF3Me, and SiF2Me2, with ground state %NO, and exciplexes with excited state 4~N 0 .The calculations favour an increasing relative stability of the complexes and exciplexes with silanes in the order SiF4 < F3SiMe < F2SiMez with, in 4 . each particular case, a geometry favouring the -SiON over the IntroductionBond indices for simple molecules such as hydrocarbons Sensitisation of NO by ~~( 6 3~~) atoms leads to 4 . r r N~ follow a pattern which correlates with the chemist's concept of which provides a route to decomposition into the observed (1) multiplicity of bonds; thus, for ethane, ethylene, and acetylene products NZ, 0 2 , and N20. The decomposition quantum yields the C-C bond indices are, respectively, 1.023, 2.032, and are markedly enhanced (2) by the methylfluorosilanes with the 2.998. Following this trend we have suggested that such bond