Theoretical study of the magnetic properties of the CoCu2O3 compound

In this paper we present a theoretical study of the magnetic properties of the CoCu2O3 compound. The magnetic effective exchange interactions and zeroth-field splitting were computed using ab initio methods, then the magnetic order and transition temperature were determined using classical Monte Carlo simulations. We showed that, unlike other members of the ACu(2)O(3) family, the presence of an additional magnetic atom, associated with a large folding of the puckered layers in the (<(a)over right, <(b)over right arrow> directions, induces a magnetic pattern based on coupled three-leg ladders, quite different from the two-leg structural ladders. The propagation vector has been found to be (q) over right arrow = (0, 1/2, 1/2). It is associated with a doubly degenerated ground state suggesting a doubling of the unit cell. The large Co2+-ion anisotropy was shown to be of crucial importance in the high transition temperature observed in this compound.