An EPR study of spin correlations and existence of ordered and disordered phases in (NBu4)2Mn2[Cu(opba)]3·6DMSO·1H2O

EPR measurements on (NBu4)2Mn2[Cu(opba)]3·6DMSO·1H2O in second harmonic mode in the 300–13 K range have shown a strong 1/T dependence of line position in the paramagnetic phase, evolution of local ordering below 40 K and a new zero-field signal in the long-range ordered phase. These features suggest: (i) existence of spin correlations from room temperature resulting in local short-range order below 40 K; and (ii) coexistence of ordered and disordered phases at 14 K. The new EPR signature at zero-field obtained at and below 15 K, is attributed to domain walls.