Force constants of SF6 from isotopic substitution

Abstract

The intramolecular force constants governing the F1u vibrational species of the SF6 molecule have been calculated from a knowledge of the isotopic shift of the bending vibration. The effects of anharmonicity on both frequencies of this species are found to be very small and the force constants are nearly as accurate as those obtained from the use of Coriolis coupling constants. A comparison with other force field calculations on this molecule suggests that the ovff model is a good approximation to the true force field. The bond dipole moment and bond moment derivative have also been calculated using the force constants obtained in this work. © 1971.