Switchable Dielectric Behavior and Order‐Disorder Phase Transition in a New Organic‐Inorganic Hybrid Compound: (CH3NH3)4[InCl6]Cl

• Published in: European journal of inorganic chemistry 2020-02, Vol.2020 (7), p.626-630
• Main Authors: Li, Min, Xu, Guan‐Cheng, Xin, Wen‐Bo, Zhang, Yin‐Qiang
• Format: Article
• Language: English
• Subjects: Dielectric materials; Hydrogen bonds; Order‐disorder; Organic‐inorganic hybrid composites; Phase transitions
• ISSN: 1434-1948; 1099-0682
• DOI: 10.1002/ejic.201901303

A new organic‐inorganic phase transition material (CH3NH3)4[InCl6]Cl (1), has been successfully synthesized and characterized. The compound undergoes a reversible first‐order phase transition at Curie temperature Tc=284 K, accompanied with a wide hysteresis of 12 K, which investigated by differential scanning calorimetry (DSC). The temperature dependence of the dielectric permittivity discloses an obvious step‐like dielectric anomaly. Single crystal X‐ray diffraction reveals that the order‐disorder transition of the [InCl6]3– anion and the methylammonium cation were the main factor drove the phase transition from high temperature phase with the space group P2/m to low temperature phase with the space group P2/n. This finding indicates that In‐based organic–inorganic hybrids compounds can be used to build phase transition materials, which broaden the way for exploring dielectric switching materials. The new organic‐inorganic hybrid compound (CH3NH3)4[InCl6]Cl has been successfully synthesized by reaction of methylammonium with indium(III) chloride tetrahydrate. It undergoes a first‐order phase transition accompanied with an obvious step‐like dielectric switching.