摘要A novel organic-inorganic hybrid phase transition compound [(C3H7)2dabco]CoBr4 with switchable dielectric property is synthesized, and the phase transition behavior was measured by DSC measurements. The DSC curves display a pair of endothermic and exothermic peaks at 230 and 212 K, confirming a reversible first-order phase transition by the calculation of entropy change and the 18 K thermal hysteresis. The structural change from P42/m at room-temperature to P42 at 100 K accompanied by a deletion of mirror plane m was determined by variable temperature single-crystal X-ray diffractions. Furthermore, switchable step-like dielectric anomalies can be observed around 230 K by the real part of dielectric constant curves. The 10-fold difference of ’ between high ’ and low ’ states make compound 1 a potential candidate for sensor and detection devices at appropriate temperature and frequencies.
Abstract：A novel organic-inorganic hybrid phase transition compound [(C3H7)2dabco]CoBr4 with switchable dielectric property is synthesized, and the phase transition behavior was measured by DSC measurements. The DSC curves display a pair of endothermic and exothermic peaks at 230 and 212 K, confirming a reversible first-order phase transition by the calculation of entropy change and the 18 K thermal hysteresis. The structural change from P42/m at room-temperature to P42 at 100 K accompanied by a deletion of mirror plane m was determined by variable temperature single-crystal X-ray diffractions. Furthermore, switchable step-like dielectric anomalies can be observed around 230 K by the real part of dielectric constant curves. The 10-fold difference of ’ between high ’ and low ’ states make compound 1 a potential candidate for sensor and detection devices at appropriate temperature and frequencies.
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2020, Vol. 39 
