Avoided crossings in potential curves of BF2+: A study of models for bonding in diatomic dications

Abstract

An ab initio study of the potential energy curves for BF²⁺ is reported. The ¹Σ⁺ state is metastable and is characterized by an unusually strong bond with a well depth of 6.06 eV. The origin of this bond is clearly traced to the interaction between the strongly bonding configuration B²⁺ + F and the repulsive configurations B⁺+F⁺. Bound metastable states are also present for ¹Π and ³Π manifolds. Dipole moments are used to assign types of bonding in each region of internuclear distance for the most important electronic states. An approximate diabatic representation is given for the two low‐lying states derived from the ¹Σ⁺ adiabatic curves. This study confirms the utility of an avoided crossing‐diabatic coupling plus polarization model for systems of intermediate polarity.