THE UNIMOLECULAR DECOMPOSITION OF METHYL CHLORIDE

Abstract

The second-order rate constant for the unimolecular decomposition of methyl chloride[Formula: see text]has been calculated on a computer by the quantum version of the Marcus–Rice theory assuming no active rotations and using the experimental activation energy. With a harmonic energy level density count the calculated rate constant is 32 times smaller than the experimental value. When correction for anharmonicity is applied, the agreement is somewhat improved but the calculated rate constant is still some 20 times too small. These results are discussed in the light of the assumptions made in the course of the calculations. It is concluded that the quantum statistical collision theory, to which the Marcus–Rice theory reduces at low pressure, is a good deal more successful than Slater's, which is in error by a factor of 105–106.