VERTICAL AND ADIABATIC IONIZATION ENERGIES AND ELECTRON-AFFINITIES OFNEW SI(N)C AND SI(N)O (N=1-3) MOLECULES

Vertical and adiabatic ionization potentials (IPs) as well as electron affinities have been calculated for SiC, Si2C, Si3C, SiO, Si2O, and S i3O using five different sophisticated ab initio methods with large ba sis sets. The geometry and harmonic frequencies have been calculated a t the second-order Moller-Plesset level. Results of the calculations u sing all five methods are in a good agreement among themselves (+/- 0. 5 eV). The calculated vertical first IPs of SiC, Si2C, Si3C, and SiO m olecules agree within 0.2 eV with experimental appearance potentials f or these species.