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Updated: Jun 5, 2025
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Effect of Alkyl Chain Length on the Magnitude of Dynamically Correlated Molecules and Dynamical Crossover in
Beibei Yao1, Marian Paluch1, Zaneta Wojnarowska1
1Silesian Center for Education and Interdisciplinary Research, Institute of Physics, University of Silesia in Katowice, 75 Pułku Piechoty 1A, Chorzów 41-500, Poland.
Abstract:
This study explores the impact of alkyl chain length on dynamic heterogeneity and dynamic crossover in alkyltriethylammonium-based ionic liquids ([TEA-R][TFSI]) with varying alkyl chain lengths (R = C6, C8, and C10). Using differential scanning calorimetry and broadband dielectric spectroscopy, we observed that these ionic liquids are excellent glassformers with notable ionic conductivity at room temperature. Furthermore, the number of dynamically correlated molecules at the glass transition temperature, reflecting the dynamic heterogeneity, is exceptionally small for TEA-R ILs and becomes more reduced with longer alkyl chains. Moreover, the temperature dependence of conductivity requires two Vogel-Fulcher-Tammann equations with distinct sets of fitting parameters for an accurate description. The crossover temperature Tb, indicating the transition to complex dynamics, increases with the alkyl chain length.
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