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Updated: May 10, 2025
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Atom Probe Tomography Analysis of Exsolved Mineral Phases
Published on: October 25, 2019
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Postdesorption Fragmentation of Tetradecane in Atom-Probe Tomography Simulated by DFT
Carolin A Dietrich1, Tim M Schwarz2, Kuan Meng2
1Institute for Theoretical Chemistry, University of Stuttgart, Pfaffenwaldring 55, Stuttgart 70569, Germany.
The Journal of Physical Chemistry. A
|April 23, 2025
Summary
Atom probe tomography (APT) reveals how organic molecules fragment under high electric fields. This study shows n-tetradecane cations break into smaller pieces, providing insights into molecular analysis.
Area of Science:
- Materials Science
- Analytical Chemistry
- Physical Chemistry
Background:
- Atom probe tomography (APT) offers atomic-resolution chemical analysis of materials.
- Understanding molecular ion behavior during APT is crucial for accurate compositional analysis.
Purpose of the Study:
- To investigate the post-desorption fragmentation of n-tetradecane under high electric fields.
- To compare simulation results with experimental APT data for organic molecules.
Main Methods:
- Computational study of n-tetradecane fragmentation dynamics.
- Analysis of molecular ion behavior under simulated APT conditions.
Main Results:
- High electric fields induce asymmetric fragmentation of n-tetradecane monocation, favoring ethyl and propyl carbocations.
- N-tetradecane dication is metastable and fragments readily under applied fields.
Conclusions:
- The study elucidates fragmentation pathways of organic molecules in APT.
- Findings aid in interpreting APT data for complex organic materials.
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