Photodissociation of HN3 at 248 nm and longer wavelength: A CASSCF study

In the present work, photodissociation of HN3 at 248 nm and longer waveleng th is investigated with the complete active space SCF (CASSCF) molecular or bital method. The stationary points on the ground- and excited-state potent ial energy surfaces are fully optimized at the CASSCF level with cc-pVDZ an d cc-pVTZ basis sets. The potential energy profiles, governing HN3 dissocia tion to NH + N-2 and H + N-3, are characterized with the multireference. MP 2 (CASPT2) algorithm. The pathways leading to different products are determ ined on the basis of the obtained potential energy surfaces of dissociation and their crossing points. A comparison is made among the present and prev ious theoretical results and experimental findings. The present study provi des an insight into the mechanism of the UV photodissociation of HN3 at a w avelength range from 355 to 248 nm.