2023MNRAS.520.5183Y

A line list for two isotopologues of aluminium monochloride, Al³⁵Cl and Al³⁷Cl, is presented covering the wavelength range <0.2 µm, J up to 400, and applicable for temperatures up to 5000 K. The line lists are built using an empirical spectroscopic model consisting of potential energy curves, spin-orbit coupling curves, electronic angular momentum curves, and Born-Oppenheimer breakdown correction curves combined with ab initio dipole moments and cover the four lowest electronic states, ${X}\, ^1\Sigma ^+$, ${A}\, ^1\Pi$, ${a}\, ^3\Pi$, and ${b}\, ^3\Sigma ^+$. Considerable problems with the assignments of some laboratory rovibronic spectra are identified. Treatment of the states lying in the continuum is discussed. The YNAT line list is available from the ExoMol data base at www.exomol.com.