Erratum: Sr2CrOsO6: End point of a spin-polarized metal-insulator transition by 5d band filling [Phys. Rev. B 75, 020404(R) (2007)]

In the search for new spintronic materials with high spin-polarization at room-temperature, we have synthesized an osmium based double perovskite with a Curie-temperature of 725 K. Our combined experimental results confirm the existence of a sizable induced magnetic moment at the Os site, supported by band-structure calculations in agreement with a proposed kinetic energy driven mechanism of ferrimagnetism in these compounds. The intriguing property of Sr2CrOsO6 is that it is at the endpoint of a metal-insulator transition due to 5d band filling, and at the same time ferrimagnetism and high-spin polarization is preserved.Comment: including corrected table

Sr2CrOsO6 End point of a spin polarized metal insulator transition by 5d band filling

In the search for new spintronic materials with high spin polarization at room temperature, we have synthesized an osmium-based double perovskite with a Curie temperature of 725 K. Our combined experimental results confirm the existence of a sizable induced magnetic moment at the Os site, supported by band-structure calculations, in agreement with a proposed kinetic-energy-driven mechanism of ferrimagnetism in these compounds. The intriguing property of Sr2CrOsO6 is that it is at the end point of a metal-insulator transition due to 5d band filling and at the same time ferrimagnetism and high-spin polarization are preserved

Radiation damage in biological material: Electronic properties and electron impact ionization in urea

Radiation damage is an unavoidable process when performing structural investigations of biological macromolecules with X-ray sources. In crystallography this process can be limited through damage distribution in a crystal, while for single molecular imaging it can be outrun by employing short intense pulses. Secondary electron generation is crucial during damage formation and we present a study in urea, as model for biomaterial. From first principles we calculate the band structure and energy loss function, and subsequently the inelastic electron cross section in urea. Using Molecular Dynamics simulations, we quantify the damage and study the magnitude and spatial extent of the electron cloud coming from an incident electron, as well as the dependence with initial energy.Comment: 6 pages, 5 figures. Several major modifications. Revised version as accepted in EPL. Corrected figures 4 and 5, corresponding to published erratu

Density matrix approach to the orbital ordering in the spinel vanadates: a case study

In this work we apply the density matrices approach to orbital ordering (OO) in order to study the OO of the spinel vanadates AV2O4 (A ≡ Zn, Cd and Mg), which is normally believed to be responsible for the structural transition from cubic to tetragonal phase observed in these compounds. The density matrices of vanadium atoms are obtained by using state-of-the-art full-potential linearized augmented plane wave method based GGA + U calculations. In the absence of spin-orbit coupling, the present study shows the existence of anti-ferro OO in the global (local octahedral) coordinate system where dxz and dyz (dxz + dyz and dxz−dyz) orbitals are mainly occupied at the neighboring V sites for all the compounds