SUBMILLIMETER-WAVE SPECTRUM AND STRUCTURE OF ACRYLONITRILE

The rotational spectrum of CH2=CHCN in its ground state and in its lowest-lying excited state was measured up to 1000 GHz. Different ways to check the assignment of the spectrum are discussed, and it is shown that the matrix of variance-decomposition proportions is very useful as a measure of the interdependence of the fitted parameters. These new data have been used to improve notably the accuracy of the rotational and centrifugal distortion (including some octic ones) constants. Finally, an ab initio structure has been calculated and a near-equilibrium structure has been estimated using offsets derived empirically. (C) 1994 Academic Press, Inc.