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Updated: Jun 7, 2025
08:12
Characterization, Quantification and Compound-specific Isotopic Analysis of Pyrogenic Carbon Using Benzene Polycarboxylic Acids BPCA
Published on: May 16, 2016
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Structural transformations and stability of benzo[a]pyrene under high pressure
Wenju Zhou1, Andrey Aslandukov1, Anastasiia Minchenkova2
1Material Physics and Technology at Extreme Conditions, Laboratory of Crystallography, University of Bayreuth, 95447 Bayreuth, Germany.
Iucrj
|November 15, 2024
Summary
High pressure reveals new forms of Benzo[a]pyrene (BaP), a common polycyclic aromatic hydrocarbon (PAH). These findings enhance understanding of how PAHs behave and remain stable under extreme conditions.
Area of Science:
- Materials Science
- Chemistry
- Geophysics
Background:
- Polycyclic aromatic hydrocarbons (PAHs), like Benzo[a]pyrene (BaP), are widespread in extraterrestrial and terrestrial environments.
- PAHs experience extreme conditions, necessitating studies on their structural behavior under pressure.
Purpose of the Study:
- To investigate the high-pressure structural transformations of Benzo[a]pyrene (BaP).
- To identify new crystalline phases and understand their stability under extreme pressure.
Main Methods:
- In situ synchrotron single-crystal X-ray diffraction up to 28 GPa.
- Density functional theory (DFT) calculations.
Main Results:
- Discovery of two new Benzo[a]pyrene (BaP) polymorphs: BaP-II (P21/c) at 4.8 GPa and BaP-III (P1) at 7.1 GPa.
- Observed abrupt structural changes during phase transitions, including alterations in intermolecular angles and unit-cell parameters.
- DFT calculations confirmed BaP-III as the most stable phase above 3.5 GPa.
Conclusions:
- The study elucidates the complex high-pressure behavior of Benzo[a]pyrene (BaP).
- Identified polymorphs and their stability provide critical data for understanding PAH behavior in extreme environments.
- Advances knowledge of structural dynamics and stability of polycyclic aromatic hydrocarbons (PAHs) under pressure.
Keywords:
benzo[a]pyrenehigh-pressure crystallographymolecular crystalsphase transitionspolycyclic aromatic hydrocarbonsMore Related Videos
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