Atomic Resonant Tunneling in the Surface Diffusion of H Atoms on Pt(111)
Abstract
The quantum motions of hydrogen (H) atoms play an important role in the dynamical properties and functionalities of condensed phase materials as well as biological systems. In this work, based on the transfer matrix method and firstprinciples calculations, we study the dynamics of H atoms on Pt(111) surface and numerically calculate the quantum probability of H transferring across the surface potential fields. Atomic resonant tunneling (ART) is demonstrated along a number of diffusion pathways. Owing to resonant tunneling, anomalous rate of transfer is predicted for H diffusion along certain path at low temperatures.The role of nuclear quantum effects (NQEs) on the surface reactions involving H is investigated, by analyzing the probabilities of barriercrossing. The effective barrier is significantly reduced due to quantum tunneling, and decreases monotonically with temperature within a certain region. For barriercrossing processes where the Arrhenius type relation applies, we show the existence of a nonzero lowtemperature limit of rate constant, which indicates the nontrivial activity of Hinvolved reactions at cryogenic conditions.
 Publication:

arXiv eprints
 Pub Date:
 August 2020
 arXiv:
 arXiv:2008.12717
 Bibcode:
 2020arXiv200812717B
 Keywords:

 Condensed Matter  Materials Science;
 Condensed Matter  Mesoscale and Nanoscale Physics;
 Physics  Chemical Physics;
 Quantum Physics
 EPrint:
 43 Pages, 7 Figures, 3 Tables