HAL CCSD
Adiabatic connection in spin-current density functional theory
Desmarais, Jacques
Flament, Jean-Pierre
Erba, Alessandro
Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM) ; Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Università degli studi di Torino = University of Turin (UNITO)
Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM) ; Université de Lille-Centre National de la Recherche Scientifique (CNRS)
International audience
ISSN: 2469-9950
EISSN: 2469-9969
Physical Review B
American Physical Society
hal-03095209
https://univ-pau.hal.science/hal-03095209
https://univ-pau.hal.science/hal-03095209
Physical Review B, 2020, 102 (23), ⟨10.1103/PhysRevB.102.235118⟩
DOI: 10.1103/PhysRevB.102.235118
info:eu-repo/semantics/altIdentifier/doi/10.1103/PhysRevB.102.235118
en
Current density
Density functional theory
Magnetic field effects
Magnetization
Matrix algebra
Quantum theory
Spin orbit coupling
[CHIM.MATE]Chemical Sciences/Material chemistry
[CHIM.POLY]Chemical Sciences/Polymers
[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry
[CHIM.ANAL]Chemical Sciences/Analytical chemistry
info:eu-repo/semantics/article
Journal articles
The spin-current density functional theory (SCDFT), when formulated in a basis of Pauli spinors, provides a proper theoretical framework for the study of materials in an arbitrarily oriented external magnetic field and/or upon inclusion of spin-dependent relativistic effects, such as spin-orbit coupling. The SCDFT is formulated in terms of the particle-number density n, the Cartesian components of the magnetization mx, my, and mz, the orbital-current density j, and the three spin-current densities Jx, Jy, and Jz, where each of these density variables depends on specific blocks of the density matrix. Exchange-correlation (xc) functionals within the SCDFT should therefore depend on all of these eight fundamental density variables: Fxc[n,mx,my,mz,j,Jx,Jy,Jz], which makes their parametrization a formidable task. Here, we formulate the adiabatic connection of the SCDFT for a treatment of exact Fock exchange in the theory. We show how the inclusion of a fraction of Fock exchange in standard functionals of the (spin) DFT (either in their collinear or noncollinear versions: Fxc[n], Fxc[n,mz] and Fxc[n,mx,my,mz]) allows for the two-electron potential to depend on all those blocks of the density matrix that correspond to the eight density variables of the SCDFT, in a sensible and yet practical way. In particular, in the local-density and generalized-gradient approximations of the SCDFT, the treatment of the current densities solely from the Fock exchange term is formally justified by the short-range behavior of the exchange hole. We discuss that the adiabatic coupling strength parameter modulates the two-electron coupling of the orbital- and spin-current densities with the particle-number density and magnetization. Formal considerations are complemented by numerical tests on a periodic model system in the presence of spin-orbit coupling and in the absence of an external magnetic field.
2020-12