A LINE LIST FOR HYDROGEN SULPHIDE (H2S)

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.

S

HH

S

HH

S

HH

C2V

Symmetric bending Symmetric stretching Asymmetric stretching

ν2 ν1 ν3

Solve for the motion of electrons

Potential Energy Surface

Dipole Moment Surface

Solve for the motion of nuclei

Spectrum

DVR3D2 program suite is used to calculate the bound ro-vibrational energy levels, wave functions, and dipole transitions intensities using Radau coordinates

MOLPRO1 programEmpirical surface

2J. Tennyson et al. DVR3D: a program suite for the calculation of rotation-vibration spectra of triatomic molecules. Comput. Phys. Commun., 163:85–116, 2004.

1H.-J. Werner et al. Molpro, version 2012.1, a package of ab initio programs, 2012. see http://www.molpro.net.

Standard deviation values for the error in the calculated ro-vibrational energy levels compared to experimental values up to 17 000 cm−1 for J = 0, 1, 2, 5 and 10. Using newly refined PES3

1. POTENTIAL ENERGY SURFACE (PES)

3V G Tyuterev et al. Chem. Phys. Lett., 348:223–234, 2001. doi: 10.1016/S0009-2614(01)01093-4.

J

Standard deviation (cm−1)

Refined PES Tyuterev et al.’s PES

0 0.19 0.24

1 0.06 0.21

2 0.07 0.21

5 0.07 0.23

10 0.19 0.24

2. DIPOLE MOMENT SURFACE (DMS)• The fundamental bands of H2S are 2 to 3 orders of magnitude weakerthan in similar triatomic such as H2O and H2Se.

• ν1 and ν3 are much weaker than ν1+ν2 , ν2+ν3 , ν1+ν3

• 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.

4Thibaud Cours et al. Ab initio dipole moment function of H2S. Chem. Phys. Lett., 331:317–322, 2000.

Transition intensities accuracy using Cours et al.’s DMS4 up to 4 000 cm-1

J ≤ 5

J ≤ 5

Transition intensities accuracy using new DMS up to 4 000 cm-1

CCSD(T) / aug-cc-pV(6+d)Z5 + corrections

5T. H. Dunning, et al revisited. J. Chem. Phys., 114:9244, 2001.

6L. R. Brown, et al J. Mol. Spectrosc., 188: 148–174, 1998.

6

1L S Rothman et al The HITRAN 2004 molecular spectroscopic database. J. Quant. Spectrosc. Radiat. Transf., 96:139–204, 2005.

21

2http://spectra.iao.ru

Terahertz spectroscopy of hydrogen sulphide

Ala’a A. A. Azzam, Sergei N. Yurchenko, Jonathan TennysonDepartment of Physics and Astronomy, University College London, London, WC1E 6BT, UK

Marie-Aline Martin-Drumel * and Olivier PiraliCNRS, UMR 8214, Institut des Sciences Mol´eculaires d’Orsay, Universit´e Paris Sud XI, Orsay,

F-91405 Orsay, France and Synchrotron SOLEIL, AILES beamline, F-91192 Gif-Sur-Yvette, France

*Present address: Laboratoire de Physico-Chimie de l’Atmosph`ere, EA 4493, Universit´e du Littotal Cˆote d’Opale, F-59140 Dunkerque, France

Journal of Quantitative Spectroscopy and Radiative Transfer

Absorption spectrum for H2S in natural abundance recorded at

SOLEIL synchrotron using a globar continuum source

Comparison for our measured H232S transition positions with

different data resources

THANK YOU

Oxygen8O

Sulphur16S

Selenium34Se