Studies on electronic structures, energetics, and electron affinities of transition metal-benzene complexes and their anions with density functional theory

A theoretical study of the equilibrium geometries, spin multiplicities, dipole moments, electron affinities, and mean bond dissociation energies of neutral Mn(Bz)m (M = Ti, V, Cr, n ≤ 2, m ≤ 2, Bz = benzene) species and their anions is carried out by means of B3LYP density functional method. The ground state geometries are presented. The spin multiplicities of MBz, M2Bz, M(Bz)2 and M2(Bz)2 systems are very different from each other. The adiabatic electron affinity (AEA) with and without ZPVE correction, the vertical electron affinity (VEA), and the vertical detachment energy (VDE) of these complexes are evaluated. The theoretical AEA is in agreement with the limited experimental data. The mean bond dissociation energies for all of these neutral complexes are also calculated to examine their relative stabilities. The order of stability of Mn(Bz)m (M = Ti, V, Cr, n ≤ 2, m ≤ 2, Bz = benzene) species is M(Bz)2 > M2(Bz)2 > M2Bz > MBz and Tin(Bz)m > Vn(Bz)m > Crn(Bz)m.