Recently Rated:
Stats
Location:
Work interests:
Affiliation/website:
Preferred contact method: Reply to post in blog/forum/group
Preferred contact language(s):
Contact:
Favourite publications:
Work interests:
Affiliation/website:
Preferred contact method: Reply to post in blog/forum/group
Preferred contact language(s):
Contact:
Favourite publications:
Founding Member
Location: aizawl
Work: Density functional theory (DFT) provides a modern tool to study the ground state properties of atoms, molecules, and solids. It has been hugely successful for electronic structure calculations of solids and molecules. It relies upon good approximations to the exchange-correlation energy as a functional of the electronic spin densities. The most commonly used in solid-state calculations today is the PBE (Perdew, Burke and Ernzerhof) version of the generalized gradient approximation (GGA), employing both the density and its gradient at each point in space. Magnetic properties are natural outputs of the calculations and itinerant magnetism can be discussed in a more quantitative way. Exchange and correlation effects in the calculations mentioned before were treated with the local spin density approximation (LSDA). More recent publications introduced the LSDA+U formalism. The LSDA+ U formalism is usually applied to systems with localized electrons such as transition metal oxides or rare earth elements. However, even though Heusler compounds are considered localized moment ferromagnets, their d electrons are itinerant. The strong electron-electron interaction seems to be problematic when it is treated in a mean field way. This strongly correlated state is better treated by a combination of LSDA and local Coulombic repulsion (U), the so-called LSDA+U method. Two main LDA+U schemes are in widespread use today: The Dudarev approach in which an isotropic screened on-site Coulomb interaction U is added, and the Liechtenstein approach in which the U and exchange (J) parameters are treated separately.
Favourite Publications: elsevier springer Taylor and Francis world scientific american physical society
Work: Density functional theory (DFT) provides a modern tool to study the ground state properties of atoms, molecules, and solids. It has been hugely successful for electronic structure calculations of solids and molecules. It relies upon good approximations to the exchange-correlation energy as a functional of the electronic spin densities. The most commonly used in solid-state calculations today is the PBE (Perdew, Burke and Ernzerhof) version of the generalized gradient approximation (GGA), employing both the density and its gradient at each point in space. Magnetic properties are natural outputs of the calculations and itinerant magnetism can be discussed in a more quantitative way. Exchange and correlation effects in the calculations mentioned before were treated with the local spin density approximation (LSDA). More recent publications introduced the LSDA+U formalism. The LSDA+ U formalism is usually applied to systems with localized electrons such as transition metal oxides or rare earth elements. However, even though Heusler compounds are considered localized moment ferromagnets, their d electrons are itinerant. The strong electron-electron interaction seems to be problematic when it is treated in a mean field way. This strongly correlated state is better treated by a combination of LSDA and local Coulombic repulsion (U), the so-called LSDA+U method. Two main LDA+U schemes are in widespread use today: The Dudarev approach in which an isotropic screened on-site Coulomb interaction U is added, and the Liechtenstein approach in which the U and exchange (J) parameters are treated separately.
Favourite Publications: elsevier springer Taylor and Francis world scientific american physical society
