Triggering the spin-crossover of Fe(phen)2(NCS)2 by a pressure pulse. Pressure and magnetic field induce ‘mirror effects’

Abstract We have studied the static and dynamic effects of pressure on the spin-transition in the temperature range of the thermal hysteresis loop for the compound Fe(phen) 2 (NCS) 2 . The high-spin fraction ( n HS ) as a function of pressure and temperature has been determined by optical reflectivity. In this compound, the pressure was found to upward shift the spin-transition temperature by 23 K per kbar. During the dynamic pressure pulse, a decrease in n HS is observed, with an irreversible (reversible) character in the descending (ascending) branch of the hysteresis loop. In this respect, pressure has a ‘mirror effect’ compared to the application of an intense and pulsed magnetic field, for which – as reported previously – an increase in n HS is observed, with an irreversible (reversible) character in the ascending (descending) branch of the hysteresis loop. To cite this article: A. Bousseksou et al., C. R. Chimie 6 (2003).