Ab initio calculations on the ground and low-lying electronic states of the Cl 3 radical: emission from Cl 3

Abstract

Broad band, low level emission is observed in the region 370–420 nm following the photolysis of Cl 2 in a flow system at a pressure of 400 Torr in the presence of nitrogen buffer gas. It is suggested that the decay of an excited electronic state of the Cl 3 radical is responsible for this emission. To support this claim a series of ab initio calculations on the Cl 3 radical were performed with 6-31G and 6-31G* basis sets at the SCF and CI levels. The calculated C 2v ground state agrees with previous calculations but a lower minimum with an asymmetric structure, probably a van der Waals state, was also found. Ab initio SCF calculations on the ground state of Cl − 3 were also performed.