GENERAL ANHARMONIC FORCE CONSTANTS OF NITROUS OXIDE

Nineteen force constants of the most general quartic force field have been determined for the nitrous oxide molecule from the spectroscopic data on N214O16, N15N14O16, N215O16, and N215O18 along with four third-order parameters, λ1, λ2, λ3, and δ which appear in the Fermi coupling off-diagonal matrix elements. It has been shown that the stretching potential of N2O is well represented by a Morse type potential and there is a close relationship between the principal stretching force constants for a given bond and those of the corresponding diatomic molecule. An effort has also been made to correlate the principal stretching force constants with the corresponding bond dissociation energies. From these force constants, the potential energy contour maps for N2O are drawn. The vibrational constants of N214O16 have been reanalyzed by applying the method originally developed for the vibrational analysis of carbon dioxide by Amat and Pimbert. The vibrational constants obtained are compared with those derived from the anharmonic force constants. © 1969.