Mixed Spin S = 1 and S = 12 Layered Lattice in Cu2 F5

Abstract

The electronic and magnetic structure, including the Heisenberg model exchange interaction parameters, was explored for the recently proposed novel cuprate Cu2F5. Using the DFT+U calculation, it is shown that the compound is formed by two types of copper ions with d9 and d8 electronic configurations. We have found a very stable antiferromagnetic ordering with strong anisotropy of exchange interaction that results in the appearance of an unusual 2D-magnetism: within the (100)-plane the exchange between the S = 1 and S = 1/2 Cu ions has almost the same strength as between the two S = 1 ions. The interplane magnetic interaction is five times weaker than the in-plane one. © 2021 American Physical Society.