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Updated: Nov 2, 2025
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High-Temperature and High-Pressure In situ Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy
Published on: October 9, 2020
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Light- and temperature-assisted spin state annealing: accessing the hidden multistability
Yan-Cong Chen1, Yan Meng1,2, Yan-Jie Dong2
1Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education, School of Chemistry, Sun Yat-Sen University Guangzhou 510275 P. R. China tongml@mail.sysu.edu.cn nizhp@mail.sysu.edu.cn.
Chemical Science
|June 14, 2021
Summary
Researchers unlocked hidden multistability in spin crossover (SCO) materials using a novel annealing process. This discovery advances the development of advanced multistate intelligent devices.
Area of Science:
- Materials Science
- Chemistry
- Physics
Background:
- Spin crossover (SCO) materials are responsive and multistable, enabling multiple spin states with external stimuli.
- SCO systems offer potential for advanced devices due to their tunable physical outputs.
Purpose of the Study:
- To investigate hidden multistability in a 2D Hofmann-type coordination polymer, [Fe(isoq)2{Au(CN)2}2].
- To clarify light- and temperature-assisted spin state transition pathways in SCO materials.
Main Methods:
- Utilized a medium-temperature annealing process after light/temperature stimulation.
- Employed magnetic, crystallographic, and Mössbauer spectral investigations.
Main Results:
- Successfully accessed hidden multistability in the spin state of the coordination polymer.
- Identified distinct spin states and elucidated transition pathways.
- Revealed excitation-relaxation and trapping-relaxation mechanisms.
Conclusions:
- The study demonstrates a novel approach to accessing hidden multistability in SCO materials.
- The findings highlight the interplay of kinetic and thermodynamic effects in SCO systems.
- This work opens new avenues for discovering multistable materials and developing intelligent devices.
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