Large curvature transmission coefficient

The use of Eq. (5-10) to evaluate the reaction rate is characterised by the calculation of Hessians for a large number of points along the MEP which are required to locate the free energy maximum and also to evaluate the curvature required for evaluation of the transmission coefficient. In view of the associated computational expense, high-level electronic structure calculations are not feasible and alternative strategies, one of which is to use a semi-empirical method, are usually employed [81]. 

A, 106,4957 (2002). Interpolated Algorithm for Large-Curvature Tunneling Calculations of Transmission Coefficients for Variational Transition State Theory Calculations of Reaction Rates. 

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