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Updated: Jun 27, 2025

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Using atomic clustering based on structural and electronic descriptors that consider surrounding environment to
Yuya Nakajima1, Takuto Ohmura2, Junji Seino1,2
1Waseda Research Institute for Science and Engineering, Tokyo, Japan.
We developed a machine learning method to group atoms based on their environments, improving the accuracy assessment of density functional theory (DFT) functionals for predicting 13C NMR chemical shifts.
Area of Science:
- Computational Chemistry
- Materials Science
- Machine Learning
Background:
- Density Functional Theory (DFT) is crucial for predicting material properties.
- Accurate evaluation of DFT functionals is essential for reliable predictions.
- Existing methods may not capture the nuances of local atomic environments.
Purpose of the Study:
- To develop a detailed method for evaluating DFT functional accuracy.
- To leverage machine learning for atomic clustering based on descriptors.
- To enhance the assessment of 13C NMR chemical shift predictions.
Main Methods:
- Utilized a machine learning-based clustering approach.
- Employed structural and electronic descriptors for atom grouping.
- Analyzed 30,436 carbon atoms from the QM9 dataset, forming 36 intuitive clusters.
- Evaluated 84 DFT functionals for 13C NMR chemical shift calculations.
Main Results:
- Successfully generated 36 distinct atomic clusters reflecting similar chemical environments.
- Demonstrated that grouping atoms by environment reduces prediction errors.
- Showcased the capability of the method to provide detailed accuracy insights.
- Identified variations in DFT functional performance across different atomic clusters.
Conclusions:
- Atomic clustering based on machine learning offers a refined approach to DFT functional evaluation.
- This method provides more granular insights into the accuracy of DFT calculations for specific chemical environments.
- The developed technique enhances the reliability of predicting 13C NMR chemical shifts.
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