Magnetic and Mossbauer investigation of the photomagnetic prussian blue analogue Na0.32CO[Fe(CN)6]0.74•3.4H2O:: Cooperative relaxation of the thermally quenched state

Thanks to thermal quenching we investigated the relaxation of the metastable state of Na0.32Co[Fe(CN)(6)](0.74)(.)3.4H(2)O at low temperature. A self-accelerated process has been observed in agreement with the cooperative character of the system, responsible for the large thermal hysteresis of the charge-transfer-induced spin transition. The mean-field analysis of the relaxation is discussed with respect to the equilibrium properties. A sizable deviation from mean-field behavior is observed at the beginning of the relaxation process, which might be attributed to a preliminary structural relaxation of the quenched state.