کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5426818 | 1395908 | 2006 | 9 صفحه PDF | دانلود رایگان |
Using all electron fully relativistic DFT calculations we have computed the EPR properties of Au atoms bound to various sites of the MgO surface. Changes in g-tensor and hyperfine coupling constants provide a way to identify the gold adsorption site and to map the surface morphology by comparison of measured and calculated EPR spectra. We found a strong reduction of the isotropic hyperfine coupling constant, aiso(Au), for adsorbed gold compared to the free atom; this reduction, which is about 45% for terrace sites, is more pronounced when Au interacts with low-coordinated sites like steps, edges and corners where it is about 60%. The reduction of aiso(Au) is accompanied by a corresponding increase of the superhyperfine interaction with the surface oxygen sites, as measured by aiso(17O). Large anisotropies in the g-tensor are computed for all sites.
Journal: Surface Science - Volume 600, Issue 12, 15 June 2006, Pages 2434-2442