Electron Orderings of Half-Filled Extended Hubbard Models with Spin- and Charge-Exchange Interaction

Abstract

The electron orderings of the half-filled extended Hubbard models (i) with anisotropic spin-exchange interactions (the t−U−J‖−J⊥ model) and (ii) with charge-exchange interaction (the t−U−I model) are discussed. In particular, we present new results concerning the phase diagrams of the model (i) in the case of uniaxial spin exchange (J‖ 6= 0) for d-dimensional hypercubic lattices (1 ≤ d ≤ ∞) and conclude about the basic effects of the particular spinand charge-exchange interaction terms (J‖, J⊥, and I) in both models.