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With the increasing research on giant dielectric materials, there is growing interest in the development of switching materials with giant dielectric properties. In this study, a novel organic–inorganic hybrid material (Et3NC2H4Br)FeCl4 was synthesized. It was characterized through differential scanning calorimetry (DSC) and in situ temperature-dependent powder X-ray diffraction (PXRD), which determined its phase transition temperature (TC) to be 362 K. Temperature-dependent dielectric measurements revealed that the material exhibited switchable dielectric properties, with the real part of the dielectric constant exceeding 106 at 500 Hz and a dielectric switching ratio surpassing 103. The ratio refers to the ratio between the high dielectric state and the low dielectric state of a step-like dielectric anomaly. Single-crystal X-ray diffraction (SCXRD) analysis confirmed that the material crystallized in the P21/c space group with a zero-dimensional structure. The optical bandgap, determined through UV-visible spectroscopy, was calculated to be 2.62 eV. Additionally, analysis using Hirshfeld surfaces and 2D fingerprint plots revealed that the predominant intermolecular interactions are H⋯Cl and H⋯H interactions. This study is anticipated to provide insights and hope for the design and application of high-temperature giant dielectric switching materials. [ABSTRACT FROM AUTHOR]

Crystal phase transformation is often accompanied by changes in corresponding physical properties. For instance, dielectric properties may undergo abrupt changes near the phase-transition temperatures. Currently, designing and synthesizing organic–inorganic hybrid materials with significant dielectric changes remains a field worth exploring. In this study, the compound [N(Et)3CH2Cl]2[MnCl4] (compound 1) was synthesized and characterized. The compound exhibited a reversible phase transition at 320 K, and dielectric permittivity anomalies were found near the phase-transition temperature. The observed changes in the space group from P1¯ (2) at LTP (below the phase-transition temperature) to P42/nmc (137) at HTP (above the phase-transition temperature) also proved an order–disorder phase transition. Significantly, compound 1 was green, and strong emission at 520 nm could be observed under ultraviolet excitation, which can be attributed to the d–d transition of the spin–orbital prohibition produced by the cations. Both dielectric and fluorescence properties of compound 1 may find applications in the fields of switchable, dielectric, and luminescent materials. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) have drawn increasing attention for their promising applications in thermal switches, data communication, and energy storage. Because of the complexity of the interactions between molecules, it is still a challenge to design PCMs with a desired high phase transition temperature (Tc). In this study, a one-dimensional hybrid perovskite of (TEACCl)PbBr3 (1, TEACCl = Et3NCH2Cl) was successfully designed and synthesized with a Tc = 390 K. Disordering of TEACCl+ on the heating process is the origin of the structural phase transition of 1 from the P21/c to P63/mmc structure. It is noted that the phase transition is associated with an excellent switchable dielectric property, which indicates that 1 has the potential to be applied to sensor equipment. After calculation, 1 is an infrequent indirect bandgap semiconductor with an energy gap of 3.57 eV. Moreover, 1 exhibits strong red fluorescence under irradiation of UV light. This work will provide guidance for designing high Tc switching materials. [ABSTRACT FROM AUTHOR]