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Updated: Jan 31, 2026

Optogenetic Phase Transition of TDP-43 in Spinal Motor Neurons of Zebrafish Larvae

Optogenetic Phase Transition of TDP-43 in Spinal Motor Neurons of Zebrafish Larvae

Published on: February 25, 2022

プラスチック結晶[(C4H9)4N]FeCl4：可逆的な秩序-無秩序相転移と熱エネルギー貯蔵の可能性

Khawla Ben Brahim¹, Imen Ibrahmi¹, Imed Kammoun¹

¹Laboratory of Spectroscopic Characterization and Optical Materials, Faculty of Sciences, University of Sfax B.P. 1171 3000 Sfax Tunisia benbrahimkhawla75@gmail.com.

|January 30, 2026

Abstract:

Alkylammonium halogenoferrates have attracted considerable attention due to their structural versatility and functional potential. Here, we report the growth of [(C₄H₉)₄N]FeCl₄ single crystals via slow evaporation under controlled conditions. X-ray powder diffraction (XRPD) confirmed the formation of a pure orthorhombic phase. Differential scanning calorimetry (DSC) revealed two reversible phase transitions between room temperature and 440 K, with a plastic crystalline state stabilized above 400 K. Temperature-controlled XRPD indicated a symmetry increase consistent with a phase transition, while Raman spectroscopy up to 423 K evidenced the reorientation of the tetrabutylammonium cation and displacement of the [FeCl₄]^- anion as the driving mechanisms. The large enthalpy changes and reversible order-disorder dynamics highlight the potential of [(C₄H₉)₄N]FeCl₄ for thermal energy storage applications. Electrical characterization, performed through complex impedance measurements in the temperature range 303-393 K and frequency range 200-1 × 10⁷ rad s^-1, confirmed the presence of two-phase transitions. The frequency-dependent AC conductivity follows Jonscher's universal power law and is governed by two hopping mechanisms: correlated barrier hopping (CBH) and non-overlapping small polaron tunneling (NSPT). Dielectric measurements further revealed relaxation processes consistent with the dynamic behavior of the cation-anion sublattice. These findings establish this hybrid halogenoferrate as a model system for probing phase-transition mechanisms in plastic crystalline materials and for designing next-generation thermal energy storage devices.

キーワード:

熱エネルギー貯蔵相転移プラスチック結晶テトラブチルアンモニウムテトラクロロ鉄(III)酸塩単結晶成長分光法粉末X線回折示差走査熱量測定電気伝導度

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Microfluidic Preparation of Liquid Crystalline Elastomer Actuators

Microfluidic Preparation of Liquid Crystalline Elastomer Actuators

Published on: May 20, 2018

Reverse Microemulsion-mediated Synthesis of Monometallic and Bimetallic Early Transition Metal Carbide and Nitride Nanoparticles

Reverse Microemulsion-mediated Synthesis of Monometallic and Bimetallic Early Transition Metal Carbide and Nitride Nanoparticles

Published on: November 27, 2015

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