Bonding in B-2 and B-2(+): Insights from full configuration interaction and valence bond studies

摘要

Full Configuration Interaction (Full-CI) and Valence Bond Self-Consistent Field (VBSCF) methods have been used to study the electronic structure and bonding in B-2 and B-2(+) molecules. The bonding analysis based on these calculations shows that the B-2 molecule is stabilised due to the formation of a double a bond, one strong a-bond together with one second weaker a-bond, and two weak it bonds. Upon ionization one It electron is removed from the system and B-2(+) is formed, which has a one electron a bond, instead of a it bond. It has been shown that a few carefully chosen VB configurations are enough to describe the bonding; with these structures, geometrical parameters as well as dissociation energies of these unusual molecular species are in agreement with full-CI results. (C) 2017 Elsevier B.V. All rights reserved.