The magnetic properties of the LaCr3(BO3)4 crystal

This article investigates the magnetic susceptibility, χ(T), of the two-phase (R32 + C2/c) crystal LaCr3(BO3)4 in the temperature range 2–300 K for two orientations of an external magnetic field. It has been established that both structural modifications of lanthanum chromium borate are ordered antiferromagnetically, with each of them having its own Neel temperature (6.5 and 8.5 K). It has been shown that at T > 60 K, the magnetic susceptibility is well described by the Curie–Weiss law with an effective magnetic moment of μeff = 3.86 μB/Cr3+ and a Curie–Weiss temperature of θ = –23 K. Within the Heisenberg spin chain model, taking into account the interchain exchange interaction, the authors have obtained the following exchange-interaction constants: an antiferromagnetic intrachain exchange (J/k = 4.8 K) and a ferromagnetic interchain exchange (J'/k = –0.28 K).