Electronic States of Difluorocarbene Calculated by Multireference Configuration Interaction Method

We investigate the geometries and energies of seven electronic states \tilde X^1\!A_1, \tilde A^1\!B_1, \tilde a^3\!B_1, \tilde B^1\!A_2, \tilde b^3\!A_2, \tilde C^1\!B_2 and \tilde c^3\!B_2 of CF_2 carbene using internally contracted multireference configuration interaction methods including Davidson correction (icMRCI+Q) with different basis sets aug-cc-pVXZ (X=T, Q, 5). For the first time, the potential energy curves of electronic states of CF_2 related to the lowest dissociation limit are calculated at the icMRCI+Q/aug-cc-pVTZ level. The ab initio results will further increase our understanding of the structures and dynamics of electronic states of CF_2 radical.