Distribution of Reaction Products. IV. Reactions Forming an Ionic Bond, M+XC (2d)

Abstract

Recent discoveries arising from crossed‐molecular‐beam studies of reactions M+XC→MX+C, in which an alkali‐metal atom M reacts with a halogen (XC≡XY) or a halide, have been examined in the light of the electron‐jump model; M+XC→M⁺+(XC)⁻→products. A very simple potential function was used to simulate reaction by the electron‐jump mechanism. The properties of this potential‐energy hypersurface were determined by the classical trajectory method. In the exploratory work described here, the particles were restricted to motion in two dimensions (2d). The effects were explored of variations in a considerable range of parameters. In the subsequent paper (Part V) the most important of these parameters will be investigated with better statistics, in 3d. From the 2d calculations it was evident that the most important parameters governing product energy distribution and angular distribution in these computations were the electron‐jump distance, the repulsive energy release between the particles comprising (XC)⁻, and the admissibility of charge migration from end to end of (XC)⁻. The M+XC reactions exemplify mixed energy release (see Part II). A simple model of mixed energy release, termed the S.H. (simple harmonic) model, is presented. The model shows that for a wide range of conditions mixed energy release can play a significant role in channeling product repulsion into vibration.