Transition moments in infrared-active fundamentals of spherical-top molecules

Abstract

The theoretical expression which relates the total strength of a vibration–rotation band of a tetrahedral or octahedral molecule to an individual line strength and to an appropriate transition electric-dipole moment is re-examined. Values of these transition moments are inferred from experimental band and line strengths. For the few molecules where direct comparisons can be made, the agreement between the values of transition moments obtained by the two methods is satisfactory. Remarkable systematics in the results are found for a variety of spherical-top molecules, which suggests that transition electric-dipole moments may be transferable from molecule to molecule for similar vibrations.