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We theoretically investigate the ground state magnetic properties of the brownmillerite phase of SrCoO2.5. Strong correlations within Co d electrons are treated within the local spin density approximations of Density Functional theory (DFT) with Hubbard U corrections (LSDAU) and results are compared with the Heyd Scuzeria Ernzerhof (HSE) functional. The parameters computed with a U value of 7.5 eV are found to match closely to those computed within the HSE functional. A G type antiferromagnetic structure is found to be the most stable one, consistent with experimental observation. By mapping the total energies of different magnetic configurations onto a Heisenberg Hamiltonian we compute the magnetic exchange interaction parameters, J, between the nearest neighbor Co atoms. The J s obtained are then used to compute the spin wave frequencies and inelastic neutron scattering intensities. Among four spin wave branches, the lowest energy mode was found to have the largest scattering intensity at the magnetic zone center, while the other modes becomes dominant at different momenta. These predictions can be tested by experimentally.
To design and discover new materials for next-generation energy materials such as solid-oxide fuel cells (SOFCs), a fundamental understanding of their ionic properties and behaviors is essential. The potential applicability of a material for SOFCs is
We demonstrate the accuracy of the hybrid functional HSE06 for computing band offsets of semiconductor alloy heterostructures. The highlight of this study is the computation of conduction band offsets with a reliability that has eluded standard densi
We study the mutual coupling of spin fluctuations and lattice vibrations in paramagnetic CrN by combining atomistic spin dynamics and ab initio molecular dynamics. The two degrees of freedom are dynamically coupled leading to non-adiabatic effects. T
The origin of the 2-dimensional electron system (2DES) appearing at the (001) interface of band insulators $rm SrTiO_3$ and $rm LaAlO_3$ has been rationalized in the framework of a polar catastrophe scenario. This implies the existence of a critical
We study the oxo-hexametallate Li$_7$TaO$_6$ with first-principles and classical molecular dynamics simulations, obtaining a low activation barrier for diffusion of $sim$0.29 eV and a high ionic conductivity of $5.7 times 10^{-4}$ S cm$^{-1}$ at room