Structural parameters of the ground states of the quasi‐stable diatomic anions CO−, BF−, and BCl− as obtained by conventional Ab Initio methods

Abstract

The experimental electron affinity (EA) of CO(X1Σ+) is −1.5 eV, signifying the metastability of the CO−(X2Π) anion. The electronic structure and bonding of CO−, BF−, and BCl− vis‐à‐vis their neutral counterparts have been studied by conventional coupled‐cluster (CCSD(T)) and multireference (MRCI) methods. Our results are in agreement with experiment for the CO/CO− system, indicating as well the metastable nature of the BF−(X2Π) and BCl−(X2Π) anions, their MRCI EAs being −0.8 ± 0.1 and −0.3 ± 0.1 eV, respectively. Our work clearly shows the usefulness of stationary state ab initio methods to the elucidation of metastable species. © 2015 Wiley Periodicals, Inc.