Vibrational-rotational Deexcitation Of HF In Collision With He

State-to-state cross sections are reported for vibrational-rotational transitions for HF in collisions with He, at collisional energies of 0.5 and 1.0 eV. These were computed within the infinite-order sudden (IOS) approximation using adiabatic, distorted-wave techniques. Values are tabulated for the vibrational-rotational deexcitation sequences (v,j)→(v-1, 0), with v=1, 2, 3, 4 and j=0-40. These quenching cross sections can be used in conjunction with IOS factorization formulas to compute VRT cross sections for final rotational states other jf=0. In addition to IOS results, vibrational quenching cross sections were computed using the much more simple breathing-sphere technique. The breathing-sphere results compare favorably to the more accurate IOS results, particularly as to energy dependence. This suggests a simple method of utilizing known quenching cross sections to predict values for different vibrational levels and/or collisional energies. © 1983 American Institute of Physics