Potential Energy Surface Including Electron Correlation for the Chemical F + H2 → FH + H I. Preliminary Surface

Abstract
Rigorous quantum mechanical calculations have been carried out for about 150 linear and 200 non‐linear geometries for the FH2 system. The contracted Gaussian basis set used consisted of four s and two p functions on fluorine and two s functions on hydrogen. The barrier height and exothermicity are poorly predicted by single configuration self‐consistent‐field calculations. However, the 214‐configuration correlated results are in qualitative agreement with experiment (low barrier height and substantial exothermicity). The reaction coordinate is discussed, and pictures of the potential surface are presented. A second series of calculations is being carried out with a larger basis set. These latter calculations yield nearly quantitative agreement with experiment for both the barrier height and exothermicity.