High-dimensional Quantum Dynamics Study on Excitation-Specific Surface Scattering including Lattice Effects of a Five-Atoms Surface Cell

TL;DR

This study uses high-dimensional quantum dynamics calculations to analyze how lattice effects influence surface scattering of CO on Cu(100), revealing excitation-dependent sticking probabilities with flexible surface atoms.

Contribution

It introduces a 21D ML-MCTDH approach with a decomposed potential energy surface to include lattice effects in surface scattering simulations.

Findings

Lattice effects decrease CO sticking probability.

Vibrational excitation of surface atoms reduces sticking.

Flexible surface modeling improves scattering predictions.

Abstract

In this work high-dimensional (21D) quantum dynamics calculations on mode-specific surface scattering of a carbon monoxide molecule on a copper (100) surface with lattice effects of a five-atom surface cell are performed through the multilayer multiconfiguration time-dependent Hartree (ML-MCTDH) method. We employ a surface model in which five surface atoms near the impact site are treated as fully flexible quantum particles while all other more distant atoms are kept at fixed locations. To efficiently perform the 21D ML-MCTDH wavepacket propagation, the potential energy surface is transferred to canonical polyadic decomposition form with the aid of a Monte Carlo based method. Excitation-specific sticking probabilities of CO on Cu(100) are computed and lattice effects caused by the flexible surface atoms are demonstrated by comparison with sticking probabilities computed for a rigid surface. The dependence of the sticking probability of the initial state of the system is studied, and it is found that the sticking probability is reduced, when the surface atom on the impact site is initially vibrationally excited.