Optical Potentials in Molecular Collisions

Inelastic transitions in molecular collisions are discussed in terms of optical (complex) potentials. Adiabatic and sudden approximations for molecular collisions are considered, as well as conditions for their validity. Numerical results obtained in an adiabatic approximation are presented for rotational and vibrational transitions in the H + H2 system, which include a study of the real and the imaginary parts of its optical potential. The relevance of optical potentials in the description of direct molecular reactions is also briefly considered.