TY  - JOUR
AU  - Zhang, Xue-Jing
AU  - Koch, Erik
AU  - Pavarini, Eva
TI  - General superexchange Hamiltonians for magnetic and orbital physics in e<sub>g</sub> and t<sub>2g</sub> systems
JO  - Physical review / B
VL  - 105
IS  - 11
SN  - 1098-0121
CY  - Woodbury, NY
PB  - Inst.
M1  - FZJ-2022-03989
SP  - 115104
PY  - 2022
AB  - Material-specific super-exchange Hamiltonians are the key to studying spin and orbital physics in strongly correlated materials. Recently, via an irreducible-tensor operator representation, we derived the orbital superexchange Hamiltonian for t<sup>1</sup><sub>2g</sub> perovskites and successfully used it, in combination with many-body approaches, to explain orbital physics in these systems. Here, we generalize our method to e<sup>n</sup><sub>g</sub> and t<sup>n</sup><sub>2g</sub> systems at arbitrary integer filling n, including both spin and orbital interactions. The approach is suitable for numerical implementations based on ab initio hopping parameters and realistic screened Coulomb interactions and allows for a systematic exploration of superexchange energy surfaces in a realistic context.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000766641700003
DO  - DOI:10.1103/PhysRevB.105.115104
UR  - https://juser.fz-juelich.de/record/910611
ER  -