Ab initio studies of dissociation pathways on the ground- and excited-state potential energy surfaces for formyl chloride (HClCO)

Potential energy surfaces of the HClCO dissociation to H+ClCO and Cl+HCO in the lowest three electronic states (S-0, S-1, and T-1) have been investiga ted with ab initio molecular orbital method at the levels of the complete a ctive space self-consistent-field, single- and multi-reference MP2. The res ults show that the C-Cl bond cleavage on the S-1 surface is the most probab le mechanism for the HClCO photodissociation at 230-320 nm. In comparison w ith formyl fluoride (HFCO), a significant difference was found in photodiss ociation dynamics between HClCO and HFCO, and this has been discussed in de tail. (C) 2001 American Institute of Physics.