Photodissociation study of 1,2-C2H4BrCl at 234 and 267 nm by the ion-velocity imaging technique

The photodissociation of 1,2-C2H4BrCl has been investigated at 234 and 267 nm using the ion-velocity imaging technique. The images of the bromine fragments show the characteristics of a direct dissociation process and the extracted anisotropy parameters indicate the molecules are mainly excited to 3Q0 state at both wavelength. A new decomposition channel on the ground state was observed. It was attributed to internal conversion from the excited electronic state to the ground state. The product quantum yields were measured to be Ф234nm(Br∗) = 0.39 and Ф267nm(Br∗) = 0.25, and the contribution of each state to the product was estimated.