Tunable Dielectric Responses Triggered by Dimensionality Modification in Organic–Inorganic Hybrid Phase Transition Compounds (C₅H₆N)Cd_nCl_2n+1 (n = 1 and 2)

Abstract

Two hybrids (CHN)CdCl (1) and (CHN)CdCl (2) were synthesized by stoichiometric regulation of reactants. 1 with a one-dimensional chain-like structure shows a step-like dielectric anomaly at around 158 K. 2 with a layered structure undergoes a prominent phase transition in the vicinity of 182 K, accompanying obvious dielectric relaxation behavior in a broad temperature range. Systematic characterization, such as differential scanning calorimetry (DSC), single-crystal X-ray diffraction, and dielectric measurements, has demonstrated that the phase transitions of 1 and 2 are both attributable to the dynamic motion of the organic cation. Significantly, dimensionality modulation triggers the tunable dielectric responses in these two compounds. Thus, regulation of the phase transition temperature and dielectric responses in the various dimensions of the structure is a potentially effective method to construct tunable dielectric phase transition materials.

High‐Temperature Reversible Phase Transition and Switchable Dielectric and Semiconductor Properties in a 2D Hybrid [(C3H12N2O)CdCl4]n

“…), following a slowly increasing slope, while a reverse process appears around 393 K for the cooling run, where the dielectric constant falls from 9.5 to 8.4 (a.u.). Relative to heat response for phase transition, dielectric constant changes is slightly lagged; this dielectric constant switched mode was also reported in other early work , , , , . Besides, similar dielectric variation law also applies to other frequencies, such as 100 kHz (Figure S4).…”

“…Nevertheless, most organic‐inorganic hybrid reversible phase transition materials (OIHPTM) still suffer a few challenges, such as, i) a low phase transition temperature (usually below or in the vicinity of room temperature), however practical applications require higher temperature such as a automatic switch for a mobile phone's baterry, so exploration of switchable materials with high reversible phase transition temperature always is a goal for physicist and chemist;, ii) a single performance, they mainly focused on ferroelectric, switchable dielectric properties, etc. and the other physical properties such as conduct electricity are seldom reported , , .…”

Room-temperature ferroelasticity and unusual sequence of phase transitions in the crystal of (N2H5)3[CdCl5]

“…Geometry parameters, such as Cd-Cl terminal , Cd-Cl bridging distances and Cd-Cl-Cd angles are comparable to those in other polymeric cadmium chloride structures that comprise (a) vertex-sharing octahedral units (see, for example, Chapuis et al, 1975;Chapuis, 1977;Lu et al, 2013;Sun et al, 2017;Wei, 1987;Willett, 1977;Yu et al, 2009); (b) face-sharing octahedral units (see, for example, Ma et al, 2006;Morosin, 1972;Peral et al, 2000). In the studied structure Cd-Cl terminal bond lengths range from 2.530 (2) Å to 2.656 (2) Å , Cd-Cl bridging bond lengths are in the range 2.6681 (18)-2.7184 (18) Å and Cd trans -Cl-Cd trans angles range between 168.77 (8) and 178.77 (9) (Table 2).…”

Above Room Temperature Reversible Phase Transition Induces Distinct Dielectric and Nonlinear Optical Switching Response Behavior in Crown-Ether-Based Supramolecular Clathrate

“…As an important class of functional materials, compounds with switchable physical properties via optical, electrical, magnetic, or mechanical manipulation are technologically important, because they can be used in a wide range of applications, including switches and memory devices [1][2][3][4][5]. Recently, a great deal of effort in this field has been devoted to the design of molecule-based materials with multiple switching effects of physical properties for potential application in the fields of digital processing, optoelectronic devices, and sensors [6][7][8].…”