Koopmans' theorem ionization potentials of methyl and silyl halides,chalcogenides, amines,and phosphines: An ab InitioSCF study

Koopmans' theorem ionization potentials have been calculated for a series of hydrides, methyls, and silyls H_nX, (CH₃)_nX, and (SiH₃)_nX (X = F, Cl, n = 1; X = O, S, n = 2; X = N, P, n = 3), together with some mixed species (MH₃)_nXH_3-n (X = N, P; M = C, Si) using ab initio SCF methods. The calculated values give excellent agreement with experimental values without the inclusion of d functions. For the chlorides, HCl, CH₃Cl, and SiH₃Cl, the values vary rather little over a wide range of basis sets, and are unaffected by the inclusion of d functions.