"UNIQUE" SETS OF POTENTIAL ENERGY CONSTANTS FOR HALOMETHANES.
Robert S. Dennen · The Knowledge Bank (The Ohio State University) · 1965
From previously observed vibrational spectral data for the chloromethanes, potential energy constant calculations have been carried out allowing the symmetrized F's to vary over a wide range and making use of the most general quadratic potential energy function of the valence force type. Unique values of one of the F's were obtained by comparison of the results for $CH_{2}Cl_{2}$ and $CD_{2}Cl_{2}$. Such a procedure enables one to obtain five of the potential energy constants uniquely. A similar calculation has been made also for the bromomethane with the available data. It is hoped to extend these calculations to the deuteriated analog when the experimental study which is now in progress is completed. The values of the constant for C-H stretching and their variation obtained in the various halomethanes will be discussed. Comparison of the other constants also will be made.