Ion-dipole molecule rate coefficients

Using the semiclassical adiabatic invariance method, extensive computations are performed on the cross sections and rate coefficients for hitting collisions between ions and linear polar molecules. The results are parameterized so that the cross sections and rate coefficients for any polarizability, dipole moment, reduced mass, and temperature can easily be calculated. Some calculations are also performed for collisions involving symmetrical top polar molecules in low (J,K) levels. The results show that the (1,1) rate coefficients are somewhat greater than are the (1,0) rate coefficients, especially at low temperatures. These results are relevant to the study of interstellar cloud chemistry because, if an exothermic reaction is possible in such chemistry, its probability of occurrence in a hitting collision is likely to be very high.