# ExoMol molecular line lists XIX: high accuracy computed hot line lists for H$_2$$^{18}$O and H$_2$$^{17}$O

## TL;DR

This paper presents high-accuracy hot line lists for water isotopologues H2-18O and H2-17O, using novel potential energy surfaces and ab initio dipole moments to predict energy levels and transitions up to high rotational states.

## Contribution

It introduces a new method combining experimental data and ab initio calculations to generate accurate line lists for water isotopologues at high energies.

## Key findings

- Extended energy range for accurate predictions.
- Line lists include transitions up to J=50 and 30,000 cm^-1.
- Data available online for use in astrophysical models.

## Abstract

Hot line lists for two isotopologues of water, \octo\ and \heto, are presented. The calculations employ newly constructed potential energy surfaces (PES) which take advantage of a novel method for using the large set of experimental energy levels for \hato\ to give high quality predictions for \octo\ and \heto. This procedure greatly extends the energy range for which a PES can be accurately determined, allowing accurate prediction of higher-lying energy levels than are currently known from direct laboratory measurements. This PES is combined with a high-accuracy, {\it ab initio} dipole moment surface of water in the computation of all energy levels, transition frequencies and associated Einstein A coefficients for states with rotational excitation up to $J=50$ and energies up to 30~000 \cm. The resulting HotWat78 line lists complement the well-used BT2 \hato\ line list (Barber et.al, 2006, MNRAS, {\bf 368}, 1087). Full line lists are made available in the electronic form as supplementary data to this article and at \url{www.exomol.com}.