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Title: Predicting Lewis Acidity: Machine Learning the Fluoride Ion Affinity of p ‐Block‐Atom‐Based Molecules
Abstract “How strong is this Lewis acid?” is a question researchers often approach by calculating its fluoride ion affinity (FIA) with quantum chemistry. Here, we present FIA49k, an extensive FIA dataset with 48,986 data points calculated at the RI‐DSD‐BLYP‐D3(BJ)/def2‐QZVPP//PBEh‐3c level of theory, including 13 differentp‐block atoms as the fluoride accepting site. The FIA49k dataset was used to train FIA‐GNN, two message‐passing graph neural networks, which predict gas and solution phase FIA values of molecules excluded from training with a mean absolute error of 14 kJ mol−1(r2=0.93) from the SMILES string of the Lewis acid as the only input. The level of accuracy is notable, given the wide energetic range of 750 kJ mol−1spanned by FIA49k. The model's value was demonstrated with four case studies, including predictions for molecules extracted from the Cambridge Structural Database and by reproducing results from catalysis research available in the literature. Weaknesses of the model are evaluated and interpreted chemically. FIA‐GNN and the FIA49k dataset can be reached via a free web app (www.grebgroup.de/fia‐gnn).  more » « less
Award ID(s):
2202693
PAR ID:
10500189
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
German Chemical Society
Date Published:
Journal Name:
Angewandte Chemie International Edition
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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