This paper presents a new uniform J-shifting approach for accurate calculat
ion of rate constant in quantum dynamics study of chemical reaction. Instea
d of using a fixed shifting constant B in the standard J-shifting approach,
the current method employs a temperature-dependent shifting constant which
is obtained through an optimization procedure at a given temperature. By u
tilizing the calculated reaction probabilities at only a few total angular
momentum values of J, the current approach automatically gives uniformly ac
curate rate constant across the entire range of temperature. Numerical stud
ies of several benchmark reaction systems, including the H + H-2, H-2 + OH
and H-2 + CN reactions, show explicitly that the uniform J-shifting approac
h is far superior to the standard J-shifting approach and it provides a rob
ust method for accurate and efficient calculation of reaction rate constant
in rigorous quantum dynamics study of chemical reaction. (C) 1999 American
Institute of Physics. [S0021-9606(99)01816-4].