Электронный каталог

Статья

Siurakshina, L.
Revising the Superexchange Model for the Planar Iridate Ba&sub(2)IrO&sub(4): from an Analytical Approach to ab initio Quantum-Chemical Computations / L.Siurakshina. – Text : electronic // Physical Review B. – 2026. – Vol. 114, No. 3. – P. 024412. – URL: https://doi.org/10.1103/9df7-k32m. – Bibliogr.: 59.

A modified spin-orbital superexchange theory is developed to derive the effective spin Hamiltonian HS governing the exchange interactions between pseudospins-1/2 on a square lattice, as occurs, for instance, in planar iridium oxide Ba&sub(2)IrO&sub(4). The procedure begins with the underlying three-orbital Hubbard model for the t&sub(2g) orbital manifold, which is first unitarily transformed to account for the strong spin-orbit interaction in all orders of the coupling constant λ, and then an explicit perturbative expansion with respect to the transformed hopping integrals and the Hund’s interaction is used. To place this novel analytical approach into a general context, a brief outline is given for the computational superexchange formalism based on the post-Hartree-Fock calculations in the framework of the cluster quantum chemistry methods. A complementary computational approach, based on the density functional theory with strong spin-orbit coupling and aimed at the extraction of a single-bond exchange parameter of the corresponding pseudospin model, is also discussed in some detail



ОИЯИ = ОИЯИ (JINR)2026
Спец.(статьи,препринты) = С 326.3 - Ферми-системы. Спиновые системы