The Mechanism of Reactions Involving Excited Electronic States II. Some Reactions of the Alkali Metals with Hydrogen

Abstract

Some chemiluminescent and quenching reactions of the alkali metals are considered. The reaction which leads to the luminescence of sodium in atomic hydrogen is seen to be adiabatic, and a model potential energy surface, constructed by the semi‐empirical method, is found to be in qualitative agreement with the experimental observations. The lowest electronic states of the system Na^*H₂ are considered in an attempt to understand the mechanism of the non‐adiabatic reaction which quenches the sodium D line. It is shown that two crossing points should occur, one of them involving a polar state. The rate of the quenching reaction is discussed in terms of the absolute reaction rate theory.