3 Aspects of magnetism in oxides 9 3.1 SrMnO3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.2 Crystal fields, moment formation and ordering . . . . . . . . . . . . . . . . . . 12 3.3 SrMnO3 revisited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 3.4 SrTcO3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 3.5...

Transition-metal oxides (TMOs) have been investigated extensively because this class of materials exhibits a fascinating array of phenomena because of a strong coupling among lattice, charge, spin, and orbital degrees of freedom. Creating a surface by breaking the symmetry is a way to disturb the coupled system, thus providing a fresh approach for studying the spin-charge-lattice coupling in th...

We investigate the frustrated magnetic interactions in cubic transition metal oxides with orbital degeneracy. The eg orbitals order easier and their ordering explains the A-type antiferromagnetic phase in KCuF3 and LaMnO3. In t2g systems the magnetic order changes at a transition from an orbital liquid to orbital ordered states. The fluctuations of t2g orbitals play a prominent role in LaVO3 an...

Mesoporous transition metal nitrides are interesting materials for energy conversion and storage applications due to their conductivity and durability. We present ordered mixed titanium-niobium (8:2, 1:1) nitrides with gyroidal network structures synthesized from triblock terpolymer structure-directed mixed oxides. The materials retain both macroscopic integrity and mesoscale ordering despite h...

Gate dielectrics comprised of nanocrystalline HfO2 in gate stacks with thin SiO2/SiON interfacial transition regions display significant asymmetries with respect to trapping of Si substrate injected holes and electrons. Based on spectroscopic studies, and guided by ab initio theory, electron and hole traps in HfO2 and other transition metal elemental oxides are assigned to O-atom divacancies, c...

We generate a series of Zr pseudopotentials and use them to calculate the properties of PbZrOs, in order to examine the relationship between pseudo-atomic properties and solid-state oxide results. We find that lattice constants and bond lengths within the oxide unit cell are quite sensitive to pseudopotential construction errors, and clear correlations emerge. These trends motivate our identifi...

We discuss the experimental photoemission and inverse photoemission of early transition metal oxides, in the light of the dynamical mean field theory of correlated electrons which becomes exact in the limit of infinite dimensions. We argue that a comprehensive description of the experimental data requires spatial inhomogeneities and present a calculation of the evolution of the spectral functio...

The oxides of many transition metals wet their own metal surface. The adhesion energy at this interface (E(adh,ox/m)) provides extra stabilization, which lowers the O2 pressure required for oxide stability as a thin film below that required for bulk-oxide stability by the factor exp[(2gamma(g/ox) - E(adh,ox/m))/(tN(ox)RT)], where gamma(g/ox) is the surface energy of the oxide, t is the oxide fi...

The orbital excitations of a series of transition-metal compounds are studied by means of optical spectroscopy. Our aim was to identify signatures of collective orbital excitations by comparison with experimental and theoretical results for predominantly local crystal-field excitations. To this end, we have studied TiOCl, RTiO3 (R=La, Sm, Y), LaMnO3, Y2BaNiO5, CaCu2O3, and K4Cu4OCl10, ranging f...