State-selective photofragment imaging ultraviolet spectroscopy of $Br_2$

Abstract

State-selective Photofragment Imaging Ultravioet Spectroscoscopy of $Br_2$ State-selective photofragment imaging is used to investigate the UV band of $Br_2$. Selectively ionized $Br(^2P_{\frac{3}{2}})$ at 250.91 and 264.78nm, and $Br(^2P_{\frac{1}{2}})$ at 264.88 and 277.78nm, respectively are projected onto a two dimensional position sensitive detector. The velocity distributions of bromine atoms prove that the excited molecular state correlates with $Br(^2P_{\frac{1}{2}}) +Br(^2P_{\frac{3}{2}})$. The images obtained and the measured (β} values (β=-0.72 at 264.88nm and -0.79 at 277.78nm) show a perpendicular transition(ΔΩ=±1). From the results the UV continuum state is predicted to be $1441(1_u)$ or 2422, $2341(1_g)$ states.

Predissociation Dynamics of IBr The IBr is excited to the B($^3Π^+_0$) and B``($O^+$) states and obtained the fluorescence. In the whole region of 630-555nm the interference of $I_2$ fluorescence is significant and to suppress this interference extra $Br_2$ is added. The measurement of decay time and the assignment of spectra are made for the $I_2$ fluorescence.