Halogen-regulating induced reversible high-temperature dielectric and thermal transitions in novel layered organic-inorganic hybrid semiconducting crystals.

Organic-inorganic hybrid metal halides for high-temperature phase transition have become increasingly popular owing to their wide operating temperature range in practical applications, e.g. , energy storage, permittivity switches and opto-electronic devices. This paper describes the subtle assembly of two new hybrid perovskite crystals, [Cl-C ₆ H ₄ -(CH ₂ ) ₂ NH ₃ ] ₂ CdX ₄ (X = Br 1; Cl 2), undergoing high- T reversible phase transformations around 335 K/356 K. Differential scanning calorimetry (DSC), differential thermal analysis (DTA) and VT PXRD tests uncover their reversible first-order phase transition behaviors. Furthermore, the compounds exhibit switchable dielectricity near T , making them potential dielectric switching materials. Hirshfeld surface analysis well discloses a distinct difference in hydrogen-bonding interaction between 1 and 2. UV spectra and computational analysis demonstrate that the compounds are a type of direct-band-gap semiconductor. This research will contribute an effective approach to the structure and development of multifunctional molecular hybrid crystals.