An efficient algorithm for capturing quantum effects in classical reactive scattering: application to D + H → HD + H

• Published in: Physical chemistry chemical physics : PCCP Vol. 25; no. 3; pp. 162 - 165
• Main Authors: Braunstein, Matthew, Bonnet, Laurent
• Format: Journal Article
• Published: 18.01.2023
• DOI: 10.1039/d2cp05108g
• ISSN: 1463-9076

Motivated by a recent semiclassical analysis of chemical reaction thresholds [Bonnet et al. , J. Chem. Phys. , 2022, 157, 094114], we present an efficient algorithm for including zero-point energy (ZPE) effects in classical reactive scattering. The algorithm is an extension of the quasi-classical trajectory (QCT) Gaussian binning method. We apply it to the astrophysically important D + H + 3 reaction, where there are significant quantum effects and where application of other methods is problematic [Braunstein et al. , Phys. Chem. Chem. Phys. , 2022, 24 , 5489]. The rate constants computed with the new, general algorithm closely match recent Ring Polymer Molecular Dynamics (RPMD) [Bulut et al. , J. Phys. Chem. A , 2019, 123 , 8766] and experimentally derived [Bowen et al. , J. Chem. Phys. , 2021, 154 , 084307] ones spanning ∼4 orders of magnitude from 70 to 1500 K. Thermal rate constant versus temperature for 1GB-Cav, ZPE-Cav, RPMD (RPMDdir: [Bulut et al. , J. Phys. Chem. A , 2019, 123 , 8766]), and experimentally derived results (Bowen [Bowen et al. , J. Chem. Phys. , 2021, 154 , 084307]).