CLASSICAL TRAJECTORY AND STATISTICAL ADIABATIC CHANNEL STUDY OF THE DYNAMICS OF CAPTURE AND UNIMOLECULAR BOND FISSION - IV - VALENCE INTERACTIONS BETWEEN ATOMS AND LINEAR ROTORS

The addition of atoms to linear molecules forming linear or nonlinear adducts is treated using standardized valence potentials. The dynamics is analyzed with a combination of classical trajectory (CT) and stati stical adiabatic channel (SACM) calculations. For classical adiabatic conditions, the two approaches coincide. The transition from adiabatic to nonadiabatic dynamics is investigated using CT calculations. The l ow-temperature adiabatic quantum range is studied by SACM. Thermal cap ture rate constants are represented in analytical form. Thermal rigidi ty factors are expressed in terms of molecular parameters such as the frequencies of transitional bending modes, the bond dissociation energ y, the rotational constant of the linear fragment, and the ratio of th e looseness and Morse parameters alpha/beta of the potential-energy su rface. The final rate expressions are of simple form suitable for dire ct practical applications. (C) 1998 American Institute of Physics.