			10min:

DYNAMICS OF LOCALIZED ANGULAR MOMENTUM AND MULTI-SURFACE ROTATIONAL ENERGY ANISOTROPY FOR INTERNAL-ROTOR MOLECULES AND POSSIBLE SYMMETRY CONVERSION EFFECTS.

JUSTIN C. MITCHELL, WILLIAM G. HARTER, Department of Physics, University of Arkansas, Fayetteville, AR 72701.

Rigid or semi-rigid rotors with attached gyroscopes approximately model dynamics and spectra of molecules with internal rotation or rovibrational coupling . Classical dynamics of axially constrained rotors are approximated by intersecting rotational-energy-surfaces (RES) that have (J-S).B.(J-S) forms in the limit of constraints that do no work. Improved semi-classical eigen-RES have avoided crossings that make concentric nested surfaces whose anisotropy determines approximate levels, symmetries and dynamics . Semi-classical eigensolutions are compared to those found by direct diagonalization. Possible application to spectra of methyl-rotor molecules are discussed.