Related papers: Correlated metals and the LDA+U method
We investigate the influence of s-d or p-d hybridization to d-band ferromagnetism to estimate the importance of hybridization for the magnetic properties of transition metals. To focus our attention to the interplay between hybridization…
We apply local orbital basis density functional theory (using SIESTA) coupled with a mapping to the Anderson impurity model to estimate the Coulomb assisted or correlated hybridization between transition metal d-orbitals and ligand…
The study of the strength of correlations in Na$_x$CoO$_2$ is extended to the x=0 end of the phase diagram where Mott insulating behavior has been widely anticipated. Inclusion of correlation as modeled by the LDA+U approach leads to a Mott…
In approximate density functional theory (DFT), the self-interaction error is an electron delocalization anomaly associated with underestimated insulating gaps. It exhibits a predominantly quadratic energy-density curve that is amenable to…
Two recent reports confirm that the newly synthesized Sr$_2$CoO$_4$ (formal oxidation state Co$^{4+}$) shows a high Curie temperature (~ 250 K), but they report different moments of 1.8 $\mu_B$ and 1 $\mu_B$ per Co. Using both commonly used…
We calculate magnetic anisotropy energy of Fe and Ni by taking into account the effects of strong electronic correlations, spin-orbit coupling, and non-collinearity of intra-atomic magnetization. The LDA+U method is used and its equivalence…
First principles methods can provide insight into materials that is otherwise impossible to acquire. Density Functional Theory (DFT) has been the first principles method of choice for numerous applications, but it falls short of predicting…
In this work using the density functional theory (DFT), we have studied the structural, electronic and magnetic properties of uranium dioxide with antiferromagnetic 1k-, 2k-, and 3k-order structures. Ordinary approximations in DFT, such as…
Density-functional theory is widely used to predict the physical properties of materials. However, it usually fails for strongly correlated materials. A popular solution is to use the Hubbard corrections to treat strongly correlated…
The stability of ferromagnetism at the surface at finite temperatures is investigated within the strongly correlated Hubbard model on a semi-infinite lattice. Due to the reduced surface coordination number the effective Coulomb correlation…
The first principles momentum dependent local ansatz wavefunction method (MLA) has been extended to the ferromagnetic state by introducing spin-dependent variational parameters. The theory is applied to the ferromagnetic Fe, Co, and Ni. It…
We have found that the local density of states fluctuations (LDOSF) in a disordered metal, detected using an impurity in the barrier as a spectrometer, undergo enhanced (with respect to SdH and dHvA effects) oscillations in strong magnetic…
A comprehensive investigation on point defects and their clustering behavior in nonstoichiometric uranium dioxide UO2+x is carried out using LSDA+U method based on density functional theory. Accurate energetic information and charge…
For more than three decades, nearly free electron elemental metals have been a topic of debate because the computed bandwidths are significantly wider in the local density approximation to density-functional theory (DFT) than indicated by…
The Korringa ratio, $\cal K$, obtained by taking an appropriate combination of the Knight shift and nuclear spin-lattice relaxation time, is calculated at finite temperature, $T$, in the three-dimensional electron gas model, including the…
Local density approximation (LDA) to the density functional theory (DFT) has continuous derivative of total energy as a number of electrons function and continuous exchange-correlation potential, while in exact DFT both should be…
The magnetic, noncollinear parametrization of Dudarev's DFT+$U$ method is generalized to fully-relativistic ultrasoft pseudopotentials. We present the definition of the DFT+$U$ total energy functional, and the calculation of forces and…
The magnetic moments per Fe atom in high-$T{_\textrm{c}}$ iron-based superconducting compounds, BaFe$_{2}$As$_{2}$ and LaFeAsO obtained from the first-principles calculation with local-spin-density approximation are much larger than those…
We study the low-temperature behavior of a magnetic impurity which is weakly coupled to correlated conduction electrons. To account for conduction electron interactions a diagrammatic approach in the frame of the 1/N expansion is developed.…
Metallic dopants have the potential to increase the mechanical strength of polycrystalline metals. These elements are expected to aggregate in regions of lower coordination, such as grain boundaries. At the grain boundaries, they can have a…