Pressure and temperature hysteresis in the spin-transition solid Fe(btr) 2 (NCS) 2 ·H 2 O, pure and diluted in Ni matrix

Abstract

Abstract The hysteresis loops of the spin transition crystalline powder Fe(btr)2(NCS)2·H2O, pure or diluted in a Ni-homologue, have been recorded as a function of temperature and pressure. The phase diagrams in p, T axes have been determined. Pressure hysteresis loops, at constant temperature, have been obtained. A pressure-induced structural change is inferred from the data of the pure compound. The possible thermal quenching of the high-pressure structural phase is evidenced. A relationship between the shapes of the temperature and pressure loops is established.