| Abstract
| - The simple carbon−carbon scission of ethane is investigated by performing quantum mechanical calculations.The approach described in this paper was developed to determine dissociation rate constants for both smalland large organic molecules, such as n-alkanes or alkyl-benzenes, for reasonable ranges of computation timeand accuracy. The methodology that we propose is based on generalized transition state theory, where transitionstates are defined along rate constant profiles and not along potential energy curves. Simulations reported inthis paper aim to validate this methodology by examining the dissociation of ethane. Calculations, performedat the DFT B3:LYP 6-31G** theory level, correctly account for the looseness of the transition state as afunction of temperature. Dissociation activation parameters obtained by this method are in good agreementwith data available in the literature. Despite the assumptions made, the order of magnitude and the specifictemperature dependence of rate constants for methyl recombination are also fairly predicted.
|
