The command MRCRS allows you to calculate the m-state resolved cross sections defined by Eqs. (14) and (28) of B. Follmeg, P. Rosmus, and H.-J. Werner, J. Chem. Phys. 93, 4687 (1990). The command line is

MRCRS,JOB,IENERG

where the input parameters are:

• JOB,IENERG The program searches for previous calculated tensor cross sections in the file Job{ienerg}.tcb, where IENERG is an integer (IENERG = 1, 2, … etc.)

The MRCRS command must have been preceded by the command TENXSC, which creates the table of tensor cross sections used.

⚠️ Note that the m-state resolved cross sections for a transition from rotational level J to J’ will be correct only if the parameter KMAX in the TENXSC command is

KMAX .ge. J+J'

MRCRS invokes the calculation of the m-state resolved cross sections appropriate to a Legendre expansion of a cylindrically symmetric distribution of the relative velocity vectors with respect to the z-axis. Here too, the calculated Legendre terms will be correct only for values of $\chi$ (the Legendre index) which are .le. the parameter LAMMAX in the previous invocation of TENXSC. The calculated m-state resolved cross sections are printed out to the file Job{ienerg}.mcs as well as to the standard output