Higher-order variations of ℓ-type doubling constants and centrifugal distortion constants for HCN and OCS

Abstract

The v- and J-dependences of the ℓ-type doubling constant q v and of the centrifugal distortion constant D v for linear XYZ molecules have been formulated by means of Amat and Nielsen's fourth-order theory of vibration-rotation interactions. Practical applications of the formulas have been carried out for HCN, OCS and their isotopic species by using anharmonic potential functions involving cubic and quartic terms.