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arXiv · 2605.14287

A quantum chemistry dataset containing S0-S1 conical-intersection structures of 259k molecules

Jiahui Zhang·Yifei Zhu·Chuqiao Feng·Yingjin Ma·Chao Xu·Zhenggang Lan
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Abstract

Conical intersections are key to photoinduced reactions, but comprehensive datasets of their structures remain rare. To address this gap, we built the QCDGE-CI dataset, which contains ground-state and minimum-energy conical-intersection structures for more than 259k small molecules with up to ten heavy atoms (C, N, O, or F). The minimum-energy conical-intersection geometries were computed using the semi-empirical OM2/MRCI method and evaluated through systematic benchmarks with an enlarged active space and CASSCF calculations. These benchmarks support the reliability of the geometries. Cheminformatics analyses further reveal the broad chemical diversity covered by the dataset. The dataset is designed to support machine-learning and data-driven studies of excited-state chemistry, including nonadiabatic processes.

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Jiahui Zhang, Yifei Zhu, Chuqiao Feng, Yingjin Ma, Chao Xu, Zhenggang Lan. 2026-09-20. A quantum chemistry dataset containing S0-S1 conical-intersection structures of 259k molecules. https://arxiv.org/abs/2605.14287

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