Direct dynamics study of the reaction path and rate constants of NH2+C2H6 -> NH3+C2H5

The title reaction is studied by ab initio molecular orbital theory. The ge ometries for the reactants, products and transition state are optimized at the UMP2/6-311 + G** level, and then the minimum energy path is built up by means of the intrinsic reaction coordinate method. In order to improve the energetics along the minimum energy path, single-point calculation is carr ied out by using Gaussian-2 theory. Furthermore, the forward and reverse ra te constants for the temperature range from 300 to 2100 K are obtained by t he canonical variational transition state theory with small-curvature tunne ling correction method. It is shown that the calculated rate constants are in good agreement with the experimental values. (C) 1999 Elsevier Science B .V. All rights reserved.