| Abstract
| - Single d-metal atoms on oxygen defects Fs and Fs+ of the MgO(001) surface were studiedtheoretically. We employed an accurate density functional method combined with cluster models, embeddedin an elastic polarizable environment, and we applied two gradient-corrected exchange-correlationfunctionals. In this way, we quantified how 17 metal atoms from groups 6−11 of the periodic table (Cu, Ag,Au; Ni, Pd, Pt; Co, Rh, Ir; Fe, Ru, Os; Mn, Re; and Cr, Mo, W) interact with terrace sites of MgO. We foundbonding with Fs and Fs+ defects to be in general stronger than that with O2- sites, except for Mn-, Re-, andFe/Fs complexes. In M/Fs systems, electron density is accumulated on the metal center in a notable fashion.The binding energy on both kinds of O defects increases from 3d- to 4d- to 5d-atoms of a given group, atvariance with the binding energy trend established earlier for the M/O2- complexes, 4d < 3d < 5d. Regardingthe evolution of the binding energy along a period, group 7 atoms are slightly destabilized compared totheir group 6 congeners in both the Fs and Fs+ complexes; for later transition elements, the binding energyincreases gradually up to group 10 and finally decreases again in group 11, most strongly on the Fs site.This trend is governed by the negative charge on the adsorbed atoms. We discuss implications for anexperimental detection of metal atoms on oxide supports based on computed core-level energies.
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