Effect of pressure on magnetic properties of mixed ferro-ferrimagnet (Ni0.38Mn0.62)3[Cr(CN)6]2.zH2O

We present the results of magnetization measurements performed on the ferro-ferrimagnetic (Ni0.38Mn0.62)3[Cr(CN)6]2.zH2O molecule-based magnet under pressures up to 0.8 GPa. Both antiferromagnetic JAF and ferromagnetic interaction JF are present in this magnet and temperature dependence of magnetization μ(T) exhibits the compensation temperature Tcomp at which the sign of the magnetization is reversed. Our results indicate that JAF dominates. The Curie temperature TC of the magnet increases with applied pressure, dTC/dp = 10.6 KGPa-1, due to strengthened JAF. The increase of the JAF is attributed to the enhanced value of the single electron overlapping integral S and the energy gap Δ of the mixed molecular orbitals t2g (Mn2+) and t2g (CrIII) induced by pressure. Magnetization processes are also affected by pressure: magnetization saturates at higher magnetic field and saturated magnetization is reduced. The compensation temperature Tcomp decreases under pressure.