Effect of surface temperature on quantum dynamics of H2 on Cu(111) using a chemically accurate potential energy surface

• Published in: The Journal of chemical physics Vol. 154; no. 10; pp. 104103 - 104120
• Main Authors: Dutta, Joy, Mandal, Souvik, Adhikari, Satrajit, Spiering, Paul, Meyer, Jörg, Somers, Mark F.
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 14.03.2021
• Subjects: Chemisorption; Mathematical analysis; Potential energy; Quantum theory; Scattering; Wave functions
• ISSN: 0021-9606; 1089-7690; 1089-7690
• DOI: 10.1063/5.0035830

The effect of surface atom vibrations on H2 scattering from a Cu(111) surface at different temperatures is being investigated for hydrogen molecules in their rovibrational ground state (v = 0, j = 0). We assume weakly correlated interactions between molecular degrees of freedom and surface modes through a Hartree product type wavefunction. While constructing the six-dimensional effective Hamiltonian, we employ (a) a chemically accurate potential energy surface according to the static corrugation model [M. Wijzenbroek and M. F. Somers, J. Chem. Phys. 137, 054703 (2012)]; (b) normal mode frequencies and displacement vectors calculated with different surface atom interaction potentials within a cluster approximation; and (c) initial state distributions for the vibrational modes according to Bose–Einstein probability factors. We carry out 6D quantum dynamics with the so-constructed effective Hamiltonian and analyze sticking and state-to-state scattering probabilities. The surface atom vibrations affect the chemisorption dynamics. The results show physically meaningful trends for both reaction and scattering probabilities compared to experimental and other theoretical results.