Ranea V A, Michaelides A, Ramírez R, de Andres P L, Vergés J A, King D A
Instituto de Ciencia de Materiales, Consejo Superior de Investigaciones Cientificas, Cantoblanco, E-28049 Madrid, Spain.
Phys Rev Lett. 2004 Apr 2;92(13):136104. doi: 10.1103/PhysRevLett.92.136104.
Based on the results of density functional theory calculations, a novel mechanism for the diffusion of water dimers on metal surfaces is proposed, which relies on the ability of H bonds to rearrange through quantum tunneling. The mechanism involves quasifree rotation of the dimer and exchange of H-bond donor and acceptor molecules. At appropriate temperatures, water dimers diffuse more rapidly than water monomers, thus providing a physical explanation for the experimentally measured high diffusivity of water dimers on Pd[111] [Science 297, 1850 (2002)]].
基于密度泛函理论计算结果，提出了一种水二聚体在金属表面扩散的新机制，该机制依赖于氢键通过量子隧穿进行重排的能力。该机制涉及二聚体的准自由旋转以及氢键供体和受体分子的交换。在适当温度下，水二聚体比水单体扩散得更快，从而为实验测得的水二聚体在Pd[111]上的高扩散率提供了物理解释[《科学》297, 1850 (2002)]。
