We present the ExoAtom database, www.exomol.com/exoatom, an extension of the ExoMol database to provide atomic line lists in the ExoMol format. ExoAtom is designed for detailed astrophysical, planetary, and laboratory applications. ExoAtom currently includes atomic data for 80 neutral atoms and 74 singly charged ions. These data are extracted from both the NIST and Kurucz databases, with 79/71 atoms/ions sourced from NIST and 38/37 atoms/ions sourced from Kurucz. ExoAtom uses the file types .all, .def, .states, .trans and .pf as fundamental components for structuring atomic data in a consistent hierarchy. The .states file contains quantum numbers, uncertainties, lifetimes, etc. The .trans file specifies Einstein A coefficients and their associated wavenumbers. The .pf file provides partition functions over a wide grid of temperatures. Post-processing of the ExoAtom data is provided by the program PyExoCross. Future development of ExoAtom will include additional ionization stages.
Cite
@article{arxiv.2512.24612,
title = {ExoAtom: A Database of Atomic Spectra in ExoMol Format},
author = {Qing-He Ni and Rujia Wang and Tianyang Xie and Jingxin Zhang and Christian Hill and Sergei N. Yurchenko and Jonathan Tennyson},
journal= {arXiv preprint arXiv:2512.24612},
year = {2026}
}