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Published on: October 31, 2019
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Pressure-induced shape and color changes and mechanical-stimulation-driven reverse transition in a one-dimensional
Die Zhang1, Boyang Fu1, Weilong He1
1School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu, 611731, Sichuan, China.
Nature Communications
|August 6, 2024
Summary
This study reveals a dynamic hybrid halide material that expands significantly under pressure. Uniquely, mechanical force, not pressure release, reverses this change, stabilizing a new phase.
Area of Science:
- Materials Science
- Crystallography
- Solid-State Chemistry
Background:
- Dynamic crystals exhibiting stimulus-responsive deformations are known, primarily in organic crystals and metal complexes.
- Low-dimensional hybrid halides possess structural similarities, including hydrogen bonds, but their dynamic properties are under-explored.
- Understanding dynamic behavior in hybrid halides is crucial for developing novel responsive materials.
Purpose of the Study:
- To investigate the dynamic behavior of one-dimensional hybrid halides under external stimuli.
- To explore pressure-induced phase transitions and their reversibility in (MV)BiBr5.
- To elucidate the structural features responsible for phase stabilization.
Main Methods:
- Hydrostatic pressure application up to 0.20 GPa.
- Structural analysis of phase transitions.
- Mechanical stimulation for transition reversal.
Main Results:
- A one-dimensional hybrid halide, (MV)BiBr5 (MV = methylviologen), exhibits an isosymmetric phase transition at 0.20 GPa.
- The transition involves a 20-30% length expansion and a color change from red to dark yellow.
- The high-pressure phase is stabilized at ambient conditions via mechanical stimulation, not decompression, indicating a metastable state.
Conclusions:
- The observed reversible phase transition and stabilization in (MV)BiBr5 highlight its potential as a dynamic material.
- Structural factors including Bi3+ lone pair activity, methylviologen cation reorientation, and new hydrogen bonds drive the transition.
- This work expands the understanding of dynamic phenomena in low-dimensional hybrid halides.
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