The use of scaled moments of inertia in experimental structure determinations of polyatomic molecules

Recently developed procedures for determining near-r _e structures (r _m ^p )from scaled ground-state moment of inertia data have been extended to general polyatomic molecules. A simple and general empirical method for correctingl _m ^p moments for the large vibration-rotation effects of deuterium substitution has been proposed and illustrated for a variety of polyatomic molecules. The correction requires utilization of a bond elongation parameter,δr _D ,whose experimental value is found to be approximately 0.003 Å. A theoretical justification of the approximation has been provided for linear triatomic molecules.