Molecules with high rotational angular momentum: a generalized ab initio approach

An outline is given of a systematic and automated computational procedure based upon our successful ab initio approach to the theoretical study of centrifugal distortions of rotating molecules and their associated energy stabilizations. Such a generalized procedure permits the ready evaluation of the centrifugal distortion spectroscopic constants for moderate-sized molecules of low or no symmetry; these molecules represent cases for which the older version of our computational procedure is unwieldy. More broadly, we explore the energies and geometries of molecules in those regions of nuclear coordinate hyperspace which are accessible by such distortions from the equilibrium geometry. A method is outlined for optimizing the geometry of a molecule in the presence of a centrifugal field which is parametrically dependent upon the rotational angular momentum. The field is not fixed for a given angular momentum, but is coupled with the geometry via the moment of inertia tensor. This development should prove to be of major benefit to both computational chemists and molecular spectroscopists, as it will advance the interplay of theoretical and experimental studies of molecular structure.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/27781/1/0000175.pd