Low‐energy molecular collisions with applications to interstellar cloud problems

Some commonly used theoretical approaches to the low‐energy molecular collision dynamics are briefly reviewed. The present status of theoretical calculations of intermolecular potential is summarized. Taking examples from the systems relevant to the physics and chemistry of the interstellar molecular clouds, recent calculations of the rotational and vibrational cross sections and rate constants are surveyed. Efforts of finding scaling and fitting laws are briefly mentioned. Recent studies of vibrationally excited H2 molecules, including collision‐induced dissociation, are reviewed. Finally, works on ion‐molecule collisions are discussed.