High magnetic field induced spin transition, H.M.F.I.S.T. effect, in [Fe0.52Ni0.48(btr)2(NCS)2]H2O

We report the effect of a high magnetic field (30 T) on the LS↔HS transition in [Fe0.52Ni0.48(btr)2(NCS)2]H2O. We have developed a new experimental set-up which allows to determine under a high pulsed magnetic field, the proportion nHS of molecules in the high spin state (S=2). The experiments, performed under quasi-static pulsed field, are based on the optical reflectivity as detection of the LS↔HS transition. The results on [Fe0.52Ni0.48(btr)2(NCS)2]H2O are reported and show that a partial spin transition (10%) may be induced by using a pulse of 30 T and confirm the previous study of Fe(Phen)2(NCS)2.