Theoretical study of the IR excitation of the ClNO molecule in a multimode laser field

We apply the multimode quasi resonant approximation to the study of the multiple excitation of a realistic molecule. We have used a random sampling method of the thermally populated states, which allows to reduce the computation time by one order of magnitude. The tedious problem of selecting the molecular states participating to the excitation process is solved recursively. Results obtained from the ClNO molecule excited by a multimode CO laser are presented as an example.