TY - JOUR

T1 - Quantum dynamics of hydrogen atoms on graphene. II. Sticking

AU - Bonfanti, M.

AU - Jackson, B.

AU - Hughes, K.H.

AU - Burghardt, I.

AU - Martinazzo, R.

N1 - Copyright (2015) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in (J. Chem. Phys. 143, 124704 (2015)) and may be found at (http://scitation.aip.org/content/aip/journal/jcp/143/12/10.1063/1.4931117).

PY - 2015/9/23

Y1 - 2015/9/23

N2 - Following our recent system-bath modeling of the interaction between a hydrogen atom and a graphene surface (M Bonfanti et al., XXX), we present the results of converged quantum scattering calculations on the activated sticking dynamics. The focus of this study is the collinear scattering on a surface at zero temperature, which is treated with high-dimensional wavepacket propagations with the multi-configuration time-dependent Hartree method. At low collision energies barrier-crossing dominates the sticking and any projectile that overcomes the barrier gets trapped in the chemisorption well. However, at high collision energies energy transfer to the surface is a limiting factor, and fast H atoms hardly dissipate their excess energy and stick on the surface. As a consequence, the sticking coefficient is maximum ($0:65) at an energy which is about one and half larger than the barrier height. Comparison of the results with classical and quasi-classical calculations shows that quantum fluctuations of the lattice play a primary role in the dynamics. A simple impulsive model describing the collision of a classical projectile with a quantum surface is developed which reproduces the quantum results remarkably well for all but the lowest energies, thereby capturing the essential physics of the activated sticking dynamics investigated

AB - Following our recent system-bath modeling of the interaction between a hydrogen atom and a graphene surface (M Bonfanti et al., XXX), we present the results of converged quantum scattering calculations on the activated sticking dynamics. The focus of this study is the collinear scattering on a surface at zero temperature, which is treated with high-dimensional wavepacket propagations with the multi-configuration time-dependent Hartree method. At low collision energies barrier-crossing dominates the sticking and any projectile that overcomes the barrier gets trapped in the chemisorption well. However, at high collision energies energy transfer to the surface is a limiting factor, and fast H atoms hardly dissipate their excess energy and stick on the surface. As a consequence, the sticking coefficient is maximum ($0:65) at an energy which is about one and half larger than the barrier height. Comparison of the results with classical and quasi-classical calculations shows that quantum fluctuations of the lattice play a primary role in the dynamics. A simple impulsive model describing the collision of a classical projectile with a quantum surface is developed which reproduces the quantum results remarkably well for all but the lowest energies, thereby capturing the essential physics of the activated sticking dynamics investigated

U2 - 10.1063/1.4931117

DO - 10.1063/1.4931117

M3 - Article

VL - 143

JO - Journal of Chemical Physics

JF - Journal of Chemical Physics

SN - 0021-9606

IS - 1124704

ER -