FOURTH-ORDER CENTRIFUGAL DISTORTION COEFFICIENTS FOR NONLINEAR TRIATOMIC MOLECULES

Abstract

We have made a study of the expressions for the ten fourth-order centrifugal distortion coefficients of the nonlinear XYZ-type molecule in the Nielsen-Amat-Goldsmith expansion of the Darling-Dennison Hamiltonian. We are not able to give the expressions for these coefficients in a form which represents a substantial simplification over previously available results so that determination of structural parameters through the analysis of fourth-order centrifugal distortion effects now appears feasible. Our expressions exhibit extensive cyclic and algebraic regularities which would indicate that they can be used with considerable confidence. Specialization of our results to the XYX-type molecule showed them to be consistent with previously published $work^{1}$ and yielded more workable expressions for that case as well.