1. International Symposium on Molecular Spectroscopy
Global frequency and intensity analysis of the v10/v7/v4/v12 band system of 12C2H4 at 10 μm using the D2h Top Data System
A. ALKADROU, M. ROTGER, GSMA, UMR 7331 CNRS-Université de Reims, Champagne-Ardenne, Moulin de la Housse, B.P. 1039, Cases 16-17, F Reims
V. BOUDON, Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Université de Bourgogne, 9 avenue Alain Savary, BP 47870, F Dijon Cedex, France
J. VANDER AUWERA, Service de Chimie Quantique et Photophysique, C.P. 160/09, Université Libre de Bruxelles, B-1050 Brussels, Belgique
International Symposium on Molecular Spectroscopy
71ST MEETING – JUNE 20-24, 2016 – CHAMPAIGN-URBANA, ILLINOIS

2. CONTENTS Introduction IR spectroscopy at ULB Theoretical model
Analysis and Discussion
Conclusion and perspectives for C2H4 spectroscopy

3. Introduction ν1(Ag) ν2(Ag) ν3(Ag) ν4(Au) ν5(B2g) ν6(B2g) 3026 cm-1
ν7(B2u)
ν8(B3g)
ν9(B3u)
ν10(B3u)
ν11(B1u)
ν12(B1u)
948.8 cm-1
939.9 cm-1
3104 cm-1
825.9 cm-1
cm-1
cm-1
IR active
Raman active
Inactive

4. FTIR Experiment at ULB HRFT IR spectra recorded at ULB in Brussel.
Resolution at 2×10-3cm-1 and room temperature.
The accuracy is better than 10-4 cm-1. #
Ptot / hPa
l / cm
T / K
Band S1
0.237
19.7
296.7 v7 S2
1.17
296.2 S3
0.674
968
293.2
v10, v4 S4
0.376
698 S5
0.133
293.1 S6
1.264
296.0
v12 S7
2.547 S8
7.518

5. Tensorial formalism D2h Top Data System/ XTDS (Dijon, France)
Group theory, Tensor formalism, Vibrational extrapolation methods.
It allows the treatment of complex spectroscopic problems
The tensorial approach provides detailed symmetry labels.
Effective Hamiltonian and transition moment operators can be systematically expanded.
The vibrational extrapolation : ΔB = Bν – B0
Allow global (simultaneous) fits

6. Tensorial formalism and analysis
Polyad structure Pn
Effective Hamiltonian P2
Effective dipole moment P1
Vibrational extrapolation method P0
M. Rotger et al. JQSRT 109 (2008)
F. Willaert et al. Mol Phys 104 (2006)
E. Rusinek et al. J Mol Spectrosc189 (1998)
V. Boudon et al. J Mol struct (2006)

7. Frequency analysis of the v7 band of 12C2H4 Experiment/Simulation

8. Frequency analysis of the v7 band of 12C2H4 Experiment/Simulation

9. Fit statistics for the line positions & intensities
Band
v10 v7 v4
v12
Global
Number of data
3100
5215
1181
1261
10757
Jmax 41 44 39 42
Kamax 18 21 15 25
drms/10-4 cm-1
2.4
2.5
3.9
1.9
2.6
Fit statistics for the line intensities
Band
v10 v7 v4
v12
Global
Number of data
339
815 10
481
1645
Jmax 35 34 30
Kamax 6 8
drms/ %
3.7
2.3
4.2
1.6
2.5

10. Fit residuals: obs-calc for line positions

11. Fit residuals: obs-calc for line intensities

12. Analysis of the v10/v7/v4/v12 bands of 12C2H4 Experiment/Simulation

13. Comparison of an observed spectrum of the v10/v7/v4 bands of ethylene with spectra calculated for 12C2H4

14. Comparison of an observed spectrum of the v10/v7/v4 bands of ethylene with spectra calculated for 12C2H4

15. Modeling the spectrum of the ν10 band of 12C2H4 at 10 μm
Observed/Calculated/HITRAN (Cauuet et al, 2000)

16. This work/HITRAN (Cauuet et al, 2000)
Modeling the spectrum of the ν10 band of 12C2H4 at 10 μm
This work/HITRAN (Cauuet et al, 2000)

17. Modeling the spectrum of the ν7 band of 12C2H4 at 10 μm
Observed/Calculated/HITRAN (Cauuet et al, 2000)

18. Modeling the spectrum of the ν12 band of 12C2H4 at 10 μm
Observed/Calculated/HITRAN (Rotger et al 2008)

19. This work/HITRAN (Cauuet et al, 2000)
Modeling the spectrum of the ν4 band of 12C2H4 at 10 μm
This work/HITRAN (Cauuet et al, 2000)

20. Conclusion and perspectives
I. Frequency & Intensity Analysis of v4/v7/v10/v12 de 12C2H4 at 10 μm
10757 line positions, RMS = 2.6 ×10-4 cm-1, 70/219 fitted parameters in frequency
1645 line intensity , RMS = 2.5 %, 17/30 fitted parameters in intensity
The first global intensity analysis of the tetrad of 12C2H4 at 10 μm.
Provides Improvement over HITRAN and GEISA for the frequency analysis.
In the future:
New high resolution IR spectra of the v4/v7/v10/v12 de 13C2H4 at 10 μm are recorded at SOLEIL synchrotron.
Frequency and intensity analysis of the v9/v11 bands of 12C2H4 at 3 μm

22. Acknowledgement International Symposium on Molecular Spectroscopy
A. ALKADROU, M. ROTGER, GSMA, UMR 7331 CNRS-Université de Reims, Champagne-Ardenne, Moulin de la Housse, B.P. 1039, Cases 16-17, F Reims
V. BOUDON, Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Université de Bourgogne, 9 avenue Alain Savary, BP 47870, F Dijon Cedex, France
J. VANDER AUWERA, Service de Chimie Quantique et Photophysique, C.P. 160/09, Université Libre de Bruxelles, B-1050 Brussels, Belgique
International Symposium on Molecular Spectroscopy
71ST MEETING – JUNE 20-24, 2016 – CHAMPAIGN-URBANA, ILLINOIS

23. This work/HITRAN (Cauuet et la, 2000)

24. Effective Hamiltonian Parameters
10757 Raies attribués, RMS = 3.0×10-4 cm-1 72/219 Paramètres Hamiltonien ajustés en fréquence Raies attribués, RMS = 2.4 % 17/30 Paramètres du moment dipolaire ajustés en intensité