Line shape parameters for HF in a bath of argon as a test of classical path models

The Neilsen and Gordon classical path formalism was successfully tested by comparison with extensive quantal calculations of HF in argon, using the same reliable interaction potential surface. Such good results were not obvious since HF-AR does not a priori appear as a favorable case for classical path methods due to the large rotational constant of the HF molecule. The quality of the predictions obtained are connected with the fact that the NG approach has relaxed the main deficiencies of other classical methods.