The Mean Amplitudes of Thermal Vibrations in Polyatomic Molecules. I. CF2=CF2 and CH2=CF2

Abstract

A normal coordinate treatment based on the potential function of Urey‐Bradley type has been applied to CF₂=CF₂ and CF₂=CH₂ molecules by taking into account the repulsions between nonbonded atoms in addition to the valence force field. The mean‐square amplitudes of thermal vibration of the atomic distances in these molecules have been calculated by the use of the normal coordinates and compared with those obtained by I. Karle and J. Karle from the electron diffraction investigation.