Bulk Crystal Growth and Single-Crystal-to-Single-Crystal Phase Transitions in the Averievite CsClCu5V2O10

TL;DR

This study reports the growth of bulk averievite crystals, investigates their structural phase transitions at 305 K and 127 K, and explores their magnetic properties, providing insights into their potential as quantum spin liquid hosts.

Contribution

It provides the first detailed analysis of bulk averievite crystal growth, clarifies the nature of its structural transitions, and examines its magnetic behavior, advancing understanding of this material's properties.

Findings

Structural transition at ~305 K from P-3m1 to P-3

Transition at ~127 K is a structural change within P-3 symmetry

Antiferromagnetic transition observed at 24 K

Abstract

Quasi-two-dimensional averievites with triangle-kagome-triangle trilayers are of interest due to their rich structural and magnetic transitions and strong spin frustration that are expected to host quantum spin liquid ground state with suitable substitution or doping. Herein, we report growth of bulk single crystals of averievite CsClCu5V2O10 with dimensions of several millimeters on edge in order to (1) address the open question whether the room temperature crystal structure is P-3m1, P-3, P21/c or else, (2) to elucidate the nature of phase transitions, and (3) to study direction-dependent physical properties. Single-crystal-to-single-crystal structural transitions at ~305 K and ~127 K were observed in the averievite CsClCu5V2O10 single crystals. The nature of the transition at ~305 K, which was reported as P-3m1-P21/c transition, was found to be a structural transition from high temperature P-3m1 to low temperature P-3 by combining variable temperature synchrotron X-ray single crystal and high-resolution powder diffraction. In-plane and out-of-plane magnetic susceptibility and heat capacity measurements confirm a first-order transition at 305 K, a structural transition at 127 K and an antiferromagnetic transition at 24 K. These averievites are thus ideal model systems for a deeper understanding of structural transitions and magnetism.