Structures and electron affinities of triatomic molecules consisting of Al, P and X (X = B, Al, Ga; C, Si, Ge; N, P, As; O, S and Se)

The structures and electronic properties of the triatomic molecules containing Al, P, X atoms (X = B, Al, Ga; C, Si, Ge; N, P, As; O, S and Se) and their anions are investigated at the B3LYP/cc-PVTZ and the B3LYP/aug-cc-PVTZ levels. The results show that the most stable structures of the anions are AlXP⁻ (X = B, C, N) and PAlX⁻ (X = S, Se), while for the neutral molecules, the most stable structures are PXAl (X = C, N and O). The order of the VDEs of the anions molecules and the AEAs of the neutral species are C < N < O < Si ≈ Ge < P ≈ As < Al = Ga < B < S ≈ Se and C < O < N < Si ≈ Ge < P ≈ As < B < Al ≈ Ga < S ≈ Se, respectively.