Ab initio and B3LYP-DFT calculations of GaP~(-) and GaP_2~(-): the electron affinities and vibrational frequencies of GaP and GaP_2

摘要

CCSD(T) and B3LYP equilibrium geometries, harmonic vibrational frequencies and electron detachment energies are reported for GaP~(-) and GaP_2~(-) has a ~(2)#SIGMA#~(+) ground state with a ~(2)#PI# state 2.30 kcal/mol above, while GaP has a ~(3)#SIGMA#~(-) ground state and a ~(3)#PI# state at 2.10 kcal/mol. The calculated adiabatic electron affiniey (AEA) of GaP is 1.94 eV. GaP_2~(-) has a ~(1)A_1 ground state. The B3LYP and CCSD(T) AEA of GaP_2~(~(2)B_2) are 1.73 and 1.80 eV, respectively. The calculated spacings between thelow-lying states and vibrational frequencies of GaP_2~(-) and GaP_2 are compared with recent experimental anion photoelectron data.