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Updated: Sep 30, 2025

Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Pressure-induced liquid-liquid transition in a family of ionic materials
Zaneta Wojnarowska1, Shinian Cheng2,3, Beibei Yao2
1Institute of Physics, the University of Silesia in Katowice, Silesian Center for Education and Interdisciplinary Research, 75 Pulku Piechoty 1A, 41-500, Chorzow, Poland. zaneta.wojnarowska@smcebi.edu.pl.
Abstract:
Liquid-liquid transition (LLT) between two disordered phases of single-component material remains one of the most intriguing physical phenomena. Here, we report a first-order LLT in a series of ionic liquids containing trihexyl(tetradecyl)phosphonium cation [P666,14]+ and anions of different sizes and shapes, providing an insight into the structure-property relationships governing LLT. In addition to calorimetric proof of LLT, we report that ion dynamics exhibit anomalous behavior during the LLT, i.e., the conductivity relaxation times (τσ) are dramatically elongated, and their distribution becomes broader. This peculiar behavior is induced by isobaric cooling and isothermal compression, with the τσ(TLL,PLL) constant for a given system. The latter observation proves that LLT, in analogy to liquid-glass transition, has an isochronal character. Finally, the magnitude of discontinuity in a specific volume at LLT was estimated using the Clausius-Clapeyron equation.
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