Should Thermostatted Ring Polymer Molecular Dynamics be used to calculate thermal reaction rates?

Abstract

We apply Thermostatted Ring Polymer Molecular Dynamics (TRPMD), a recently-proposed approximate quantum dynamics method, to the computation of thermal reaction rates. Its short-time Transition-State Theory (TST) limit is identical to rigorous Quantum Transition-State Theory, and we find that its long-time limit is independent of the location of the dividing surface. TRPMD rate theory is then applied to one-dimensional model systems, the atom-diatom bimolecular reactions H+H${}_2$, D+MuH and F+H${}_2$, and the prototypical polyatomic reaction H+CH${}_4$. Above the crossover temperature, the TRPMD rate is virtually invariant to the strength of the friction applied to the internal ring-polymer normal modes, and beneath the crossover temperature the TRPMD rate generally decreases with increasing friction, in agreement with the predictions of Kramers theory. We therefore find that TRPMD is approximately equal to, or less accurate than, Ring Polymer Molecular Dynamics (RPMD) for symmetric reactions, and for certain asymmetric systems and friction parameters closer to the quantum result, providing a basis for further assessment of the accuracy of this method.

13 pages, 7 figures, 2 tables. Minor alterations and corrections to the previous version in light of referees' comments

References in corpus (8)

• Accurate sampling using Langevin dynamics
• Efficient stochastic thermostatting of path integral molecular dynamics
• How to remove the spurious resonances from ring polymer molecular dynamics
• Boltzmann-conserving classical dynamics in quantum time-correlation functions: Matsubara dynamics
• Relation of centroid molecular dynamics and ring-polymer molecular dynamics to exact quantum dynamics
• On the Consistency of Approximate Quantum Dynamics Simulation Methods for Vibrational Spectra in the Condensed Phase
• Exact quantum statistics for electronically nonadiabatic systems using continuous path variables
• Non-oscillatory flux correlation functions for efficient nonadiabatic rate theory

Cited by in corpus (9)

• Chemical Reaction Rates from Ring Polymer Molecular Dynamics: Theory and Practical Applications
• Competing quantum effects in the free energy profiles and diffusion rates of hydrogen and deuterium molecules through clathrate hydrates
• Simultaneous Deep Tunneling and Classical Hopping for Hydrogen Diffusion on Metals
• Deriving the exact nonadiabatic quantum propagator in the mapping variable representation
• How to obtain thermostatted ring polymer molecular dynamics from exact quantum dynamics and when to use it
• Thermal quantum time-correlation functions from classical-like dynamics
• The low temperature D${}^{+}$ + H${}_2$ $\to$ HD + H${}^{+}$ reaction rate coefficient: a ring polymer molecular dynamics and quasi-classical trajectory study
• Which Algorithm Best Propagates the Meyer-Miller-Stock-Thoss Mapping Hamiltonian for Non-Adiabatic Dynamics?
• On the electronic path integral normal modes of the Meyer-Miller-Stock-Thoss representation of nonadiabatic dynamics