TY  - JOUR
AU  - Dutta, Rajesh
TI  - Ab-initio DFT＋ U study on the electronic correlation in multiferroic XY-antiferromagnetic Ba$_2$CoGe$_2$O$_7$
JO  - Journal of magnetism and magnetic materials
VL  - 596
SN  - 0304-8853
CY  - Amsterdam
PB  - North-Holland Publ. Co.
M1  - FZJ-2024-05292
SP  - 171955 -
PY  - 2024
N1  - Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
AB  - Ab-initio density functional theory (DFT)+U has been used to study the spin-resolved electronic band structure and the partial density of states of the multiferroic XY-antiferromagnetic Ba$_2$CoGe$_2$O$_7$. Using the constrained random-phase approximation (cRPA) method, the value of Hubbard U and Hund’s coupling 𝐽H has been determined and plugged into the further dynamical mean field theory (DMFT) calculations. The strong metalligand hybridization between Co-3d and O-2p orbitals in the CoO$_4$ tetrahedron has been demonstrated via DFT and DFT+DMFT calculations. The calculated indirect band gap in the antiferromagnetic state without and with U (=5 eV) correction is found to be 0.67 and 2.71 eV, respectively. The highest calculated ordered magnetic moment of 2.7 𝜇𝐵/Co$^{2+}$ is close to the reported experimental value. The presented DFT calculations based on the different orbital models brings the underlying strong electronic correlation in the Ba$_2$CoGe$_2$O$_7$.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:001221007700001
DO  - DOI:10.1016/j.jmmm.2024.171955
UR  - https://juser.fz-juelich.de/record/1030419
ER  -