Resonance enhanced multiphoton ionization time-of-flight (REMPI-TOF) study of tetrachloroethylene photodissociation at 235 nm: Role of bound π-σC-Cl∗ state

In one-color REMPI-TOF experiment, the photodissociation dynamics of tetrachloroethylene has been studied by probing the chlorine atom photofragments, namely, Cl (2P3/2) and Cl∗ (2P1/2), using 2 + 1 REMPI scheme in the 234-236 nm region. We have determined the centre-of-mass photofragment speed distribution, recoil anisotropy parameter (β), and the spin-orbit branching ratio for chlorine atom elimination channels. The β is well characterized by a value of ∼0.0, within the experimental uncertainties. Two components, namely, the fast and the slow, are observed in the translational energy distributions of Cl and Cl∗. The average translational energies for the Cl and Cl∗ channels for the fast components are 17.6 ± 1.9 and 14.0 ± 1.7 kcal/mol, while, that for the slow components are 2.2 ± 1.0 and 3.2 ± 1.0 kcal/mol, respectively. To understand the nature of the dissociative potential energy surface involved in the chlorine atom formation channel, detailed theoretical calculations are performed using Time-dependent Density Functional Theory (TD-DFT) method.