Variational transition state theory for activated chemical reactions in solution

An approach is outlined for including solvent effects in variational transition state theory calculations of rate constants for activated chemical reactions in solution. The focus is on methods capable of first-principles predictions of reaction rate constants from interatomic potential energy surfaces. The approach separates the system into a cluster model that is treated explicitly and the ‘solvent’ that is treated approximately, and includes both equilibrium solvation effects on interaction energies and non-equilibrium effects that enter through a solvent friction model. We discuss methods used to included quantum-mechanical effects on bound vibrational motions and quantum-mechanical effects on motion along a reaction coordinate (e.g. quantum tunnelling).