Study on the photodissociation of methylene iodide at 277 and 304 nm

Abstract

Photodissociation of $CH_2I_2$ at 277 and 304 nm has been studied utilizing state-selective photofragment translational spectroscopy. These wavelengths are correlated to second $B_1$ transition. The $I^*$ quantum yields at 277 and 304 nm are 0.37 and 0.17, respectively. This shows that curve crossing exists. The anisotropy parameters observed at 277 nm are $<\beta(I^*)>=0.8\pm0.1$ and $<\beta(I)>=0.6\pm0.1$. At 304 nm, These are \beta(I^*)>=0.5\pm0.1$ and $<\beta(I)>=0.6\pm0.1$. The translational energy distribution of recoil fragments show that a large fraction of available energy partitions to internal energy $(<E_{int}>/E_{avl}\approx0.75)$ at two wavelengths.