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In recent years, phase change materials (PCMs) have received extensive attention because of their applications in many fields, such as construction, semiconductor, energy and intelligent response switch. Organic‐inorganic hybrid materials (OIHMs) are wide applied in the preparation of PCMs due to their controllability of organic and inorganic components. In this study, we successfully synthesized an organic‐inorganic hybrid material (BTTD)MnCl4 (compound 1, BTTD=[(CH3)2NCH2Cl(CH2)3CH2ClN(CH3)2]. The purity of compound 1 was confirmed by PXRD. The crystal structure of compound 1 was analyzed at 300 K, 381 K and 400 K. The three different crystal structures prove the phase change of compound 1. According to the result of differential scanning calorimeter (DSC), the phase transition of compound 1 is reversible. Moreover, the measured bandgap (Eg) of 1 is 2.25 eV. The dielectric constant of compound 1 fluctuates near 370 K, indicating the changes of electrical properties, so compound 1 can be used to cut off circuit. This temperature is close to the boiling point of water under standard ambient conditions. Therefore, this work provides a new direction for the design of intelligent response switch for electric kettle. [ABSTRACT FROM AUTHOR]

Host‐guest inclusion materials serve as an ideal model for designing phase transition materials. The typical host molecule, 18‐crown‐6 (1, 4, 7, 10, 13, 16‐hexaoxacyclo‐octadecane), is known for its strong coordination with amino compounds through N−H⋅⋅⋅O hydrogen‐bonding interactions, attracting the attention of numerous scientific researchers. This study presented the successful synthesis and characterization of two host‐guest inclusion materials, [(trans‐4‐aminocyclohexanol)(18‐crown‐6)][ClO4] (1) and [(trans‐4‐aminocyclohexanol)(18‐crown‐6)][BF4] (2). Both compounds 1 and 2 underwent reversible phase changes at temperatures of 312 K/305 K and 322 K/314 K, respectively. In this article, crystal structures, thermal properties, optical properties and analyses of intermolecular interactions were discussed in details. Our endeavors are believed to have made a contribution to the advancement of phase change materials. [ABSTRACT FROM AUTHOR]

Molecular optical‐dielectric duple bistable switches are photoelectric (dielectric and fluorescent) multifunctional materials that can simultaneously convert optical and electrical signals in one device for seamless integration. However, exploring optical‐dielectric duple channels of dielectric and photoluminescence is still a bigger challenge than single dielectric or photoluminescence bistable ones, which are hardly reported but probably will be heavily researched owing to the new generation artificial intelligence development needs in the future. Herein, a new optical‐dielectric duple bistable switches material, [(CH3)3NCH2CH3]2MnCl4 (I), was obtained by a simple method for volatilization of solvents. Variable temperature single crystal X‐ray analysis indicates that material I has a reversible bistable structure (order‐disorder structure phase transition) corresponding to switching "ON′′ and "OFF′′. Unlike the single dielectric bistable structures that were previously reported, material I also own bistable features in terms of fluorescence property. This material enriches the specific examples of photoelectric duple function switch materials and facilitates the development of required devices. [ABSTRACT FROM AUTHOR]

Piezoelectric materials are a class of important functional materials applied in high‐voltage sources, sensors, vibration reducers, actuators, motors, and so on. Herein, [(CH3)3S]3[Bi2Br9](1) is a brilliant semiconducting organic–inorganic hybrid perovskite‐type non‐ferroelectric piezoelectric with excellent piezoelectricity. Strikingly, the value of the piezoelectric coefficient d33 is estimated as ≈18 pC N−1. Such a large piezoelectric coefficient in non‐ferroelectric piezoelectric has been scarcely reported and is comparable with those of typically one‐composition non‐ferroelectric piezoelectrics such as ZnO (3pC N−1) and much greater than those of most known typical materials. In addition, 1 exhibits semiconducting behavior with an optical band gap of ≈2.58 eV that is lower than the reported value of 3.37 eV for ZnO. This discovery opens a new avenue to exploit molecular non‐ferroelectric piezoelectric and should stimulate further exploration of non‐ferroelectric piezoelectric due to their high stability and low loss characteristics. As easy as pie: A semiconducting organic–inorganic hybrid perovskite‐type non‐ferroelectric piezoelectric with excellent piezoelectricity is reported. The value of the piezoelectric coefficient d33 is estimated as ≈18 pC N−1. Such a large piezoelectric coefficient in non‐ferroelectric piezoelectric has been scarcely reported. Furthermore, [(CH3)3S]3[Bi2Br9] exhibits semiconducting behavior with an optical band gap of ≈2.58 eV. [ABSTRACT FROM AUTHOR]

Switchable materials have developed greatly, because of their potential applications in many fields, such as data storage and dielectric devices, while the "ON"/"OFF" of the dielectric effect in polycrystalline materials to achieve high contrast is still a great challenge, which gradually become one of the research hotspots in the materials science and electronics. Herein, we report a prominent dielectric switch of (TMCM)2Hg2Cl6 (1, TMCM = trimethylchloromethyl ammonium), with a high phase transition temperature (Tc) of 405.8 K and an extremely high contrast of ca. 14. Such a breakthrough is elucidated from the highly disordered TMCM and the severely deformed of Hg2Cl6 in high temperature phase. By understanding the properties of superior dielectric, a feasible switch mechanism can be constructed to inject new vitality into the field of molecular medium switch. An organic‐inorganic polycrystalline dielectric switch, [(trimethylchloromethyl ammonium)2Hg2Cl6], shows an extremely high contrast of ca. 14. [ABSTRACT FROM AUTHOR]

Abstract: The perovskite structure is rich in ferroelectricity. In contrast, ferroelectric antiperovskites have been scarcely confirmed experimentally since the discovery of M3AB‐type antiperovskites in the 1930s. Ferroelectricity is now revealed in an organic–inorganic hybrid X3AB antiperovskite structure, which exhibits a clear ferroelectric phase transition 6/mmmF6mm with a high Curie point of 480 K. The physical properties across the phase transition are obviously changed along with the symmetry requirements, providing solid experimental evidence for the ferroelectric phase transition. More interestingly, the discovered antiperovskite shows intense photoluminescence and triboluminescence properties. The confirmation of the triboluminescent ferroelectric antiperovskite will open new avenues to explore excellent optoelectronic properties in the antiperovskite family. [ABSTRACT FROM AUTHOR]

The rational selection of ligands is vitally important in the construction of new organic–inorganic hybrid three‐dimensional perovskite complexes. As part of an exploration of perovskite‐type materials, two new Na–I compounds based on the piperazine ligand, namely poly[piperazinediium [tri‐μ‐iodido‐sodium]], {(C4H12N2)[NaI3]}n, 1, and catena‐poly[tris(piperazinediium) [[triiodidosodium]‐μ‐iodido] triiodide monohydrate], {(C4H12N2)3[NaI4]I3·H2O}n, 2, have been synthesized by adjusting the stoichiometric ratio of sodium iodide and piperazine, and were characterized by single‐crystal X‐ray diffraction. In the crystal structures of 1 and 2, each NaI cation is linked to six I atoms, but the compounds show completely different configurations. In 1, the structure includes a perovskite‐like array of vertex‐sharing NaI6 octahedra stretching along the direction of the three axes, and each piperazinediium dication is enclosed in the NaI3 perovskite cage. However, in 2, each NaI atom bridges a single I atom to form a one‐dimensional linear chain, and complex intermolecular hydrogen bonds connect these one‐dimensional chains into a three‐dimensional supramolecular network. [ABSTRACT FROM AUTHOR]

As part of an exploration of new coordination polymers, a cadmium-dicyanamide complex, namely poly[benzyltriethylammonium [tri-μ-dicyanamido-κ6 N1: N5-cadmium(II)]], {(C13H22N)[Cd(C2N3)3]} n, has been synthesized by the reaction of benzyltriethylammonium bromide, cadmium nitrate tetrahydrate and sodium dicyanamide in aqueous solution, and characterized by single-crystal X-ray diffraction at room temperature. In the crystal structure, each CdII cation is coordinated by six nitrile N atoms from six anionic dicyanamide (dca) ligands to furnish a slightly distorted octahedral geometry. Neighbouring CdII cations are linked by dicyanamide bridges to construct a two-dimensional anionic layer coordination polymer. One amide N atom in the bridging dca ligand is disordered over two sites. The cations lie between the anionic frameworks and there are no hydrogen-bond interactions between the cations and anions. The organic cations are not involved in the formation of the supramolecular network. [ABSTRACT FROM AUTHOR]