Theoretical studies on magnetic interaction in one-dimensional CunBrm (S=1/2) chains

Abstract Theoretical calculations for molecular-based magnetic materials have been carried out and successfully revealed magnetic interaction. Recently, Sugimoto and his co-workers reported synthesis and experimental studies for salts of TTF-derivative donors and Cu n Br m (S = 1/2) chains. In these crystals, their magnetic properties depend on structure changing. In this paper, we focus on magnetic interaction in one- dimensional Cu n Br m chains. Here, we introduced the universal model structure for their real crystals and four parameters (r, a, b and c ) in it can fix the structure. The J ab values under each parameter value were studied by using of UHF, UB3LYP and UCCSD(T) methods. Magnetic interactions in all shapes of Cu n Br m chains were investigated.