A complete active-space self-consistent-field study on cubic N-8

Complete Active-Space Self-Consistent-Field (CAS-SCF) calculations for cubic N-8 are presented. We studied the N-8<->4 N-2 reaction in D-4h symmetry and found its energy release and activation barrier with three different atomic basis sets. The energy release far this reaction is predicted to be around 526 kcal/mol, while the energy barrier to dissociation is estimated about 159 kcal/mol. These results are in substantial agreement with previous ab initio estimates.