Knowledge Bank

Fluorescence of $NO2$ excited by He-Cd 442 nm laser radiation is found to exhibit a spectrum characteristic of perpendicular transitions from several levels belonging to the $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}B1$ vibronic state with $K\prime >0$. The lifetimes of these levels are substantially greater than those given previously for $K\prime$ = 0 levels of the $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}B1$ state. The present results support the mechanism of lifetime lengthening by the Renner interaction of the $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}B1$ and $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}A1$ components of the linear $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Pi u$.