A L INE L IST FOR H YDROGEN S ULPHIDE (H 2 S) Ala’a A. A. Azzam J. Tennyson and S. Yurchencko Department of Physics and Astronomy, University College London, UK

Colourless gas. very poisonous. Flammable. It has very bad odour.  In volcanic gases.  natural gas.  some well waters.  from the bacterial breakdown of organic matter in the absence of oxygen. SHH SHHSHH C 2V Symmetric bending Symmetric stretching Asymmetric stretching ν2ν2 ν1ν1 ν3ν3

Solve for the motion of electrons Potential Energy Surface Dipole Moment Surface Solve for the motion of nuclei Spectrum D VR 3 D 2 program suite is used to calculate the bound ro-vibrational energy levels, wave functions, and dipole transitions intensities using Radau coordinates M OLPRO 1 program Empirical surface 2 J. Tennyson et al. DVR3D: a program suite for the calculation of rotation-vibration spectra of triatomic molecules. Comput. Phys. Commun., 163:85–116, H.-J. Werner et al. Molpro, version , a package of ab initio programs, see

Standard deviation values for the error in the calculated ro-vibrational energy levels compared to experimental values up to cm −1 for J = 0, 1, 2, 5 and 10. Using newly refined PES 3 1.P OTENTIAL ENERGY SURFACE (PES) 3 V G Tyuterev et al. Chem. Phys. Lett., 348:223–234, doi: /S (01) J Standard deviation (cm −1 ) Refined PESTyuterev et al.’s PES

2.D IPOLE MOMENT SURFACE (DMS) The fundamental bands of H 2 S are 2 to 3 orders of magnitude weaker than in similar triatomic such as H 2 O and H 2 Se. ν 1 and ν 3 are much weaker than ν 1 +ν 2, ν 2 +ν 3, ν 1 +ν 3 P-branch (ΔJ=-1) regions of the fundamental bands are much weaker than R- branch (ΔJ=1) regions.

The effect of the core-electrons correlation and relativistic corrections on the dipole moment ab initio calculations. L. Lodi, et al. A new ab initio ground-state dipole moment surface for the water molecule. J. Chem. Phys., 128:044304, 2008.

4 Thibaud Cours et al. Ab initio dipole moment function of H 2 S. Chem. Phys. Lett., 331:317–322, Transition intensities accuracy using Cours et al.’s DMS 4 up to cm -1 J ≤ 5

Transition intensities accuracy using new DMS up to cm -1 CCSD(T) / aug-cc-pV(6+d)Z 5 + corrections 5 T. H. Dunning, et al revisited. J. Chem. Phys., 114:9244, 2001.

6 L. R. Brown, et al J. Mol. Spectrosc., 188: 148–174,

1 L S Rothman et al The HITRAN 2004 molecular spectroscopic database. J. Quant. Spectrosc. Radiat. Transf., 96:139–204,

Terahertz spectroscopy of hydrogen sulphide Ala’a A. A. Azzam, Sergei N. Yurchenko, Jonathan Tennyson Department of Physics and Astronomy, University College London, London, WC1E 6BT, UK Marie-Aline Martin-Drumel * and Olivier Pirali CNRS, UMR 8214, Institut des Sciences Mol´eculaires d’Orsay, Universit´e Paris Sud XI, Orsay, F Orsay, France and Synchrotron SOLEIL, AILES beamline, F Gif-Sur-Yvette, France * Present address: Laboratoire de Physico-Chimie de l’Atmosph`ere, EA 4493, Universit´e du Littotal Cˆote d’Opale, F Dunkerque, France Journal of Quantitative Spectroscopy and Radiative Transfer

Absorption spectrum for H 2 S in natural abundance recorded at SOLEIL synchrotron using a globar continuum source

Comparison for our measured H 2 32 S transition positions with different data resources

T HANK YOU

Oxygen 8 O Sulphur 16 S Selenium 34 Se