Observation of the pressure dependent reversible enhancement of T _c and loss of the anomalous constricted hysteresis for [Ru ₂(O₂CMe)₄]₃[Cr(CN)₆]

The pressure dependences of the temperature and field, dependent magnetization, and powder X-ray diffraction patterns were reported to acquire information with respect to this anomalous hysteresis. In addition to the reversible increase in the specified temperature with increasing pressure, the shape of the hysteretic M(H) curves qualitatively changes with increasing pressure. The observed behavior is attributed to an increase in the coupling between the structurally independent ferrimagnetic lattices. The unusual transition in the shape of the hysteresis suggests that the interlattice interaction changes from antiferromagnetic to ferromagnetic, and thus is pressure-induced metamagnetic-like transition. The origin of this unusual transition decreases the bond distances that increase the orbital overlaps increasing the inter-lattice superexchange that leads to the observed increased at 33 K.