Diffracted X-ray blinking reveals signature crystal polymorph dynamics in 1,2,3,5-Tetrabromobenzene
Keegan McGehee1,2,3, Koichiro Saito2, Ryo Fukaya4
1National Institute of Advanced Industrial Science and Technology (AIST), 6-2-3 Kashiwanoha, Kashiwa, 277- 0882, Chiba, Japan.
Scientific Reports
|March 25, 2025
Summary
Diffracted X-ray blinking (DXB) reveals distinct crystalline dynamics in 1,2,4,5-tetrabromobenzene (TBB) polymorphs. Faster lattice fluctuations in the γ-phase and increased molecular motion near phase transitions offer new insights into TBB
Area of Science:
- Materials Science
- Solid-State Chemistry
- Crystallography
Background:
- 1,2,4,5-tetrabromobenzene (TBB) exhibits polymorphic behavior with distinct crystalline phases.
- Mechanically responsive crystals are crucial for advanced material applications.
- Understanding crystalline dynamics is key to predicting material properties.
Purpose of the Study:
- To investigate the time-resolved crystalline dynamics of 1,2,4,5-tetrabromobenzene (TBB) polymorphs.
- To differentiate between the β- and γ-phases of TBB using diffracted X-ray blinking (DXB).
- To explore molecular motion and lattice dynamics near phase transition temperatures.
Main Methods:
- Utilized diffracted X-ray blinking (DXB) to probe ms-s timescale crystalline dynamics.
- Analyzed fluctuations in d-spacing between lattice planes for different TBB polymorphs.
- Correlated observed dynamics with temperature-dependent phase transitions.
Main Results:
- DXB successfully distinguished between γ- and β-phase polymorphs of TBB.
- Faster d-spacing fluctuations were observed in the γ-phase compared to the β-phase.
- A significant spike in molecular motion rate was detected near the phase transition temperature.
Conclusions:
- DXB provides a novel method for characterizing subtle differences in crystalline dynamics.
- The findings offer deeper insight into anisotropic lattice softening and strain accumulation in TBB.
- This study serves as a foundation for investigating complex mechanically responsive crystal behaviors.
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