ExoMol line lists -- LI. Molecular line list for lithium hydroxide (LiOH)

TL;DR

This paper presents the first comprehensive molecular line list for lithium hydroxide (LiOH), covering over 331 million transitions, to aid in its detection in stellar and exoplanetary atmospheres, applicable up to 3500 K.

Contribution

The authors developed the first extensive line list for LiOH using high-level ab initio calculations, enabling future spectroscopic detection of this molecule in astronomical environments.

Findings

Line list contains over 331 million transitions.

Applicable for temperatures up to approximately 3500 K.

Provides data for potential detection of LiOH in exoplanet atmospheres.

Abstract

A new molecular line list for lithium hydroxide ($^{7}$Li$^{16}$O$^{1}$H) covering wavelengths $\lambda > 1 \mu$m (the 0-10000 cm$^{-1}$ range) is presented. The OYT7 line list contains over 331 million transitions between rotation-vibration energy levels with total angular momentum up to $J=95$ and is applicable for temperatures up to $T\approx 3500$ K. Line list calculations are based on a previously published, high-level \textit{ab initio} potential energy surface and a newly computed dipole moment surface of the ground $\tilde{X}\,^1\Sigma^+$ electronic state. Lithium-containing molecules are important in a variety of stellar objects and there is potential for LiOH to be observed in the atmospheres of exoplanets. This work provides the first, comprehensive line list of LiOH and will facilitate its future molecular detection. The OYT7 line list along with the associated temperature- and pressure-dependent opacities can be downloaded from the ExoMol database at www.exomol.com and the CDS astronomical database.