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

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.