The photodissociation of cadmium iodide

Abstract

A molecular beam of CdI₂ molecules was photodissociated by a dye laser at 278 and 300 nm and also by a filtered Hg–Xe lamp. The time of flight distributions obtained with the polarized laser light are anisotropic, as is the distribution obtained with the lamp. The overall conclusion is that the first absorption band of CdI₂ is a superposition of a parallel band dissociating to I* (²P_1/2 atoms and CdI(X ²Σ) molecules and a perpendicular band dissociating to I(²P_3/2) and CdI(X ²Σ). In spite of this complexity an effort is made to decompose the translational energy distribution into one for each exit channel, with the result that the available energy (aside from that appearing as electronic energy of I*) is distributed ∼40%–50% as kinetic energy of fragments.