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The electronic properties of the FeO and CoO single layer thin films on Pt(111) were examined by core-level soft x-ray spectroscopy. These oxygen terminated films are bilayer-thick and isostructural Pt, Fe-Co, and O atoms stacked with small lateral shifts due an incommensurate relation with Pt(111). Probing occupied and unoccupied states projected on the oxygen atoms revealed states at the Fermi level, suggesting orbital mixing with the metal substrate, and also indicated an anisotropy in transition metal-oxygen bonding geometry. The differences in the core-level spectral features were attributed to the substrate induced modification of the charge transfer energy and with an additional valence electron on Co.

We use x-ray spectroscopy and density functional theory to investigate the hydrogenation-induced electronic structure changes in graphene on Pt(111). The atom-specific properties of the spectroscopy allow for a direct projection of the band structure onto the carbon atoms; this was compared with the calculated density of states. Instead of the generally expected band opening behavior, we observe states at the Fermi level in the carbon-projected density of states. Hydrogenation is accompanied by pinning of the graphene to the substrate through the formation of local C--Pt bonds which cause the graphene layer to become metallic upon hydrogenation.

The unoccupied and occupied \ensuremath{\sigma} and \ensuremath{\pi} bands of graphene on Pt(111) were measured using near-edge x-ray absorption spectroscopy (XAS) and resonant inelastic x-ray scattering (RIXS) at the carbon $K$ edge. Elemental specificity and crystal-momentum conservation allows for detection of the dispersive band structure. In addition to features arising from the band structure of free-standing graphene, signatures of symmetry breaking were identified in XAS and in RIXS for excitation around the Fermi level. These additional features are proposed to derive from weak graphene-substrate interactions which manifest as substrate hybridization and surface umklapp processes due to Moir\'e superlattice vectors.

The atomic structure of the thin SiO2 film on a Mo(112) substrate has been determined based on a combination of density functional theory calculations and high-quality experimental data obtained from scanning tunneling microscopy, infrared reflection absorption spectroscopy, and x-ray photoelectron spectroscopy. The film consists of a honeycomblike, two-dimensional network of corner-sharing [SiO4] tetrahedra. One oxygen atom of each tetrahedron binds to the Mo(112) substrate and is located in a bridge position between Mo atoms located in rows protruding from the metal surface. The other three oxygen atoms form Si-O-Si bonds with the neighboring tetrahedra.

The atomic structure of the thin SiO2 film on a Mo112 substrate has been determined based on a combination of density functional theory calculations and high-quality experimental data obtained from scanning tunneling microscopy, infrared reflection absorption spectroscopy, and x-ray photoelectron spectroscopy. The film consists of a honeycomblike, two-dimensional network of corner-sharing SiO4 tetrahedra. One oxygen atom of each tetrahedron binds to the Mo112 substrate and is located in a bridge position between Mo atoms located in rows protruding from the metal surface. The other three oxygen atoms form Si-O-Si bonds with the neighboring tetrahedra.