Abstract
We derive an expression for the effective mass along the reaction coordinate in a chemically reacting system. This expression is used in two convenient algorithms for including quantum mechanical effects on the reaction coordinate into transition-state theory or generalized transition-state theory. One algorithm is based on a uniform semiclassical approximation; the other is based on a parabolic approximation to the effective potential. Examples are presented to show that the theory accurately accounts for reaction-path-curvature effects on the tunneling contributions to the reactions H + H2, D + D2, and D + H2. Although the derivation, and hence expected reliability, of the new methods is most valid for systems with small reaction-path curvature, the methods are generally applicable and should provide useful accuracy even for medium-curvature and some large-curvature systems.
Original language | English (US) |
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Pages (from-to) | 3019-3023 |
Number of pages | 5 |
Journal | Journal of Physical Chemistry |
Volume | 85 |
Issue number | 21 |
DOIs | |
State | Published - Jan 1 1981 |