ExoMol molecular line lists -- XLII: Rovibronic molecular line list for the low-lying states of NO

TL;DR

This paper presents an updated, highly accurate rovibronic line list for nitric oxide (NO), covering its low-lying states and complex spectral regions, useful for atmospheric and astronomical research.

Contribution

It provides a comprehensive, high-accuracy line list for NO's lowest four doublet states, incorporating empirical and theoretical data for improved spectral modeling.

Findings

Updated NO line list with extensive spectral data

Covers complex B-C state interactions in UV region

Enables better atmospheric and astronomical NO analysis

Abstract

An accurate line list, called XABC, is computed for nitric oxide which covers its pure rotational, vibrational and rovibronic spectra. A mixture of empirical and theoretical electronic transition dipole moments are used for the final calculation of $^{14}\mathrm{N}^{16}\mathrm{O}$ rovibronic $\mathrm{A}\,^2\Sigma^+$ -- $\mathrm{X}\,^2\Pi$, $\mathrm{B}\,^2\Pi$ -- $\mathrm{X}^2\Pi$ and $\mathrm{C}\,^2\Pi$ -- $\mathrm{X}\,^2\Pi$ which correspond to the $\gamma$, $\beta$ and $\delta$ band systems, respectively, as well as minor improvements to transitions within the $\mathrm{X}\,^2\Pi$ ground state. The work is a major update of the ExoMol NOname line list. It provides a high-accuracy NO ultraviolet line list covering the complicated regions where the $\mathrm{B}\,^2\Pi$-$\mathrm{C}\,^2\Pi$ states interact. XABC provides comprehensive data for the lowest four doublet states of NO in the region of $\lambda > 160 ~ \mathrm{nm}$ ($\tilde{\nu} < 63~000~\mathrm{cm}^{-1}$) for the analysis of atmospheric NO on Earth, Venus or Mars, other astronomical observations and applications. The data is available via www.exomol.com.