Potential Function of NF3

Abstract

An approximate potential function has been determined for NF₃ by using the four fundamental frequencies, the experimentally determined rotational distortion constant D_J, and physical arguments based on the absolute intensity results. Use has also been made of an argument proposed by Polo and Wilson based on a comparison of NF₃ with the isoelectronic molecule CF₃H. The rotational distortion constants have been calculated as a function of the force field using the method of Kivelson and Wilson. Explicit formulas are given for the change in moment of inertia with symmetry coordinate for an XY₃(C_3v) type molecule. Using the approximate potential function, values of the valence type force constants and the rotational distortion constant D_K have been calculated.