ExoMol molecular line lists XXXV: a rotation-vibration line list for hot ammonia

TL;DR

This paper introduces a comprehensive hot ammonia line list, CoYuTe, with 16.9 billion transitions, improving previous data for temperatures up to 1500 K and covering a broad spectral range, validated against experimental data.

Contribution

The paper presents the CoYuTe line list for $^{14}$NH$_3$, constructed with an accurate potential energy surface and ab initio dipole moment, significantly expanding and refining previous ammonia spectral data.

Findings

Excellent agreement with experimental data below 6000 cm$^{-1}$

Line list covers up to 20000 cm$^{-1}$ and 1500 K

Contains 16.9 billion transitions

Abstract

A new hot line list for $^{14}$NH$_3$ is presented. The line list CoYuTe was constructed using an accurate, empirically refined potential energy surface and a CCSD(T)/aug-cc-pVQZ ab initio dipole moment surface of ammonia, previously reported. The line list is an improvement of the ammonia line list BYTe [Yurchenko et al., Mon. Not. R. Astron. Soc., 413, 1828 (2011)]. The CoYuTe line list covers wavenumbers up to 20000 cm$^{-1}$, i.e. wavelengths beyond 0.5 $\mu$m for temperatures up to 1500 K. Comparisons with the high temperature experimental data from the literature show excellent agrement for wavenumbers below 6000 cm$^{-1}$. The CoYuTe line list contains 16.9 billion transitions and is available from the ExoMol website (www.exomol.com) and the CDS database.