Jiang Hongyan, Tao Xuecheng, Kammler Marvin, Ding Feizhi, Wodtke Alec M, Kandratsenka Alexander, Miller Thomas F, Bünermann Oliver
Department of Dynamics at Surfaces, Max-Planck-Institute for Biophysical Chemistry, Am Faßerg 11, 37077 Göttingen, Germany.
Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.
J Phys Chem Lett. 2021 Feb 25;12(7):1991-1996. doi: 10.1021/acs.jpclett.0c02933. Epub 2021 Feb 17.
We study nuclear quantum effects in H/D sticking to graphene, comparing scattering experiments at near-zero coverage with classical, quantized, and transition-state calculations. The experiment shows H/D sticking probabilities that are indistinguishable from one another and markedly smaller than those expected from a consideration of zero-point energy shifts of the chemisorption transition state. Inclusion of dynamical effects and vibrational anharmonicity via ring-polymer molecular dynamics (RPMD) yields results that are in good agreement with the experimental results. RPMD also reveals that nuclear quantum effects, while modest, arise primarily from carbon and not from H/D motion, confirming the importance of a C atom rehybridization mechanism associated with H/D sticking on graphene.
我们研究了氢/氘在石墨烯上吸附的核量子效应，将近零覆盖度下的散射实验与经典计算、量子化计算及过渡态计算进行了比较。实验表明，氢/氘的吸附概率彼此无法区分，且明显小于考虑化学吸附过渡态零点能位移时预期的值。通过环聚合物分子动力学（RPMD）纳入动力学效应和振动非谐性后，得到的结果与实验结果高度吻合。RPMD还揭示，核量子效应虽然不大，但主要源于碳原子而非氢/氘的运动，证实了与氢/氘在石墨烯上吸附相关的碳原子重新杂化机制的重要性。
