EPR properties of Au atoms adsorbed on various sites of the MgO(100) surface from relativistic DFT calculations

Gold atoms and clusters on MgO(100) films; an EPR and IRAS study

“…Additional insight into the physics of the system can be obtained by comparing the values of the magnetic parameters with calculated ones presented in Table 1 [25]. The calculated g-and hyperfine-components show a qualitative agreement with the experimentally determined values.…”

“…In terms of the hyperfine interaction, the calculations nicely reproduce the dominating isotropic hyperfine component for the interaction with the Au nucleus, which is reduced by about a factor of 2 ($1400 MHz vs. 3053 MHz [26]) as compared to the free atoms. However, the absolute value of the isotropic hyperfine coupling constant is overestimated by about 15% in contrast to the free atom where the theoretical approach is significantly more accurate [17,25]. In contrast to that the dipolar part of the hyperfine interaction is very small, both in experiment as well as in theory.…”

“…The polarization leads to a reduced s contribution of the unpaired electron wave-function. Consequently, the spin-density on the Au nucleus is reduced, which is reflected by a smaller isotropic hyperfine interaction [17,25]. The absence of a significant charge transfer between the Au atoms and the MgO surface implies that the spin density is almost completely on the Au atoms.…”

Oxide‐Supported Gold Clusters and Nanoparticles in Catalysis: A Computational Chemistry Perspective

“…While metal surfaces, characterized by a high degree of electron delocalization, provide an almost uniform potential energy landscape to coordinate metal adatoms, adsorption and nucleation on oxide surfaces is substantially influenced by the presence of point defects . Indeed, on the (100) surface of MgO it was proven by means of DFT calculations that the binding energy of a single gold atom is remarkably larger on point defects, such as F‐centres, or extended defects, such as step or corners, compared to the regular and defect‐free terrace . The stronger binding ability of oxygen vacancies towards metals has been proven based on non‐contact AFM measurements.…”

CO interaction with Au atoms adsorbed on terrace, edge and corner sites of the MgO(100) surface. Electronic structure and vibrational analysis from DFT

“…However, the deposition on topological defects, such as steps, edges and corners, has received much less attention [7,17]. These low-coordinated sites are found to be more reactive than terrace on both oxide and metal surfaces [18][19][20].…”