Vibrations of Tetrahedral Pentatomic Molecules. Part I. Potential Energy. Part II. Kinetic Energy and Normal Frequencies of Vibration

Abstract

Part I. It is shown that the most general potential energy function consistent with tetrahedral symmetry involves five force constants, also that with a suitable choice of variables this expression may be written in a quite simple form convenient for the discussion of different types of vibration. Special cases of potential energy such as the "valence" force and the central force cases involving less than five force constants are considered and their connection with the general case discussed.