Variation of the resonance width of HOCl(6νOH) with total angular momentum:: Comparison between ab initio theory and experiment

Complex L-2 calculations of the variation of (very narrow) resonance widths of the 6 nu(OH) state of HOCl with total angular momentum are reported, using a recently developed, accurate ab initio potential energy surface [S. Skokov, J. M. Bowman, and K. A. Peterson, J. Chem. Phys. 109, 2662 (1998)]. The calculations are carried out within the adiabatic rotation approximation for the overall rotation and a truncation/recoupling method for the vibrational states. Comparisons with recent double-resonance experiments of the Rizzo and Sinha groups are made. The variation of resonance width with J for K=0 is shown to be due to rotation-induced coupling of the 6 nu(OH) state with a dense set of states with large excitation in the dissociative coordinate. (C) 1999 American Institute of Physics. [S0021-9606(99)02820-2].