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Updated: Mar 6, 2026
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Influence of aliovalent substitution on structure and dynamics in sodium halide Na3-2x Y1-x Nb x Cl6 solid
Brian B Phan1, Tso Shuen2, Dmitry Vrublevskiy1
1Department of Chemistry, University of Alberta Edmonton Alberta T6G 2G2 Canada vladimir.michaelis@ualberta.ca.
Abstract:
Sodium halide solid electrolytes are garnering increased interest because of their synthetic flexibility to incorporate a variety of cations, thereby altering their structure and properties. Aliovalent substitution is said to increase ionic conductivity by promoting polyanion rotation. Herein, we synthesise and assess a series of Na3-2x Y1-x Nb x Cl6, probing their complex structures using complementary powder X-ray diffraction and variable-temperature 1D and 2D solid-state nuclear magnetic resonance spectroscopy. The bond-valence energy landscapes of the end members are visualised to reveal potential sodium-ion transport pathways. A structural threshold is reached for Na2Y0.5Nb0.5Cl6, revealing a limit for niobium polyhedral distortion while the unit cell volume is retained up to 50% Nb substitution. Na2Y0.5Nb0.5Cl6 shows the greatest RT ionic conductivity enhancement in the series, from 10-11 S cm-1 to 10-5 S cm-1.
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