α-CrO(0001)的几何结构与羟基分压的函数关系。

Geometry of α-CrO(0001) as a Function of HO Partial Pressure.

作者信息

Ahmed M H M, Torrelles X, Treacy J P W, Hussain H, Nicklin C, Wincott P L, Vaughan D J, Thornton G, Lindsay R

机构信息

Corrosion and Protection Centre, School of Materials, The University of Manchester , Sackville Street, Manchester, M13 9PL, U.K.

Institut de Ciència de Materials de Barcelona (CSIC) , Campus UAB, 08193 Bellaterra, Spain.

出版信息

J Phys Chem C Nanomater Interfaces. 2015 Sep 17;119(37):21426-21433. doi: 10.1021/acs.jpcc.5b04607. Epub 2015 Aug 24.

DOI:10.1021/acs.jpcc.5b04607

PMID:26877825

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC4729357/

Abstract

Surface X-ray diffraction has been employed to elucidate the surface structure of α-CrO(0001) as a function of water partial pressure at room temperature. In ultra high vacuum, following exposure to ∼2000 Langmuir of HO, the surface is found to be terminated by a partially occupied double layer of chromium atoms. No evidence of adsorbed OH/HO is found, which is likely due to either adsorption at minority sites, or X-ray induced desorption. At a water partial pressure of ∼30 mbar, a single OH/HO species is found to be bound atop each surface Cr atom. This adsorption geometry does not agree with that predicted by calculations, which may be a result of some differences between the experimental conditions and those modeled.

摘要

利用表面X射线衍射来阐明α-CrO(0001)在室温下作为水蒸气压函数的表面结构。在超高真空下，暴露于约2000朗缪尔的HO后，发现表面由部分占据的铬原子双层终止。未发现吸附的OH/HO的证据，这可能是由于在少数位点吸附，或X射线诱导解吸。在约30毫巴的水蒸气压下，发现每个表面Cr原子顶部结合有单个OH/HO物种。这种吸附几何结构与计算预测的不一致，这可能是实验条件与建模条件之间存在一些差异的结果。