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-51687 Reims V. BOUDON, Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Université de Bourgogne, 9 avenue Alain Savary, BP 47870, F-21078 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
CONTENTS Introduction IR spectroscopy at ULB Theoretical model Analysis and Discussion Conclusion and perspectives for C2H4 spectroscopy
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 2988.6 cm-1 1442.4 cm-1 IR active Raman active Inactive
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
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
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) 952-962 F. Willaert et al. Mol Phys 104 (2006) 273-292 E. Rusinek et al. J Mol Spectrosc189 (1998) 64-73. V. Boudon et al. J Mol struct 780-781 (2006) 124-133
Frequency analysis of the v7 band of 12C2H4 Experiment/Simulation
Frequency analysis of the v7 band of 12C2H4 Experiment/Simulation
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
Fit residuals: obs-calc for line positions
Fit residuals: obs-calc for line intensities
Analysis of the v10/v7/v4/v12 bands of 12C2H4 Experiment/Simulation
Comparison of an observed spectrum of the v10/v7/v4 bands of ethylene with spectra calculated for 12C2H4
Comparison of an observed spectrum of the v10/v7/v4 bands of ethylene with spectra calculated for 12C2H4
Modeling the spectrum of the ν10 band of 12C2H4 at 10 μm Observed/Calculated/HITRAN (Cauuet et al, 2000)
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)
Modeling the spectrum of the ν7 band of 12C2H4 at 10 μm Observed/Calculated/HITRAN (Cauuet et al, 2000)
Modeling the spectrum of the ν12 band of 12C2H4 at 10 μm Observed/Calculated/HITRAN (Rotger et al 2008)
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)
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
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-51687 Reims V. BOUDON, Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Université de Bourgogne, 9 avenue Alain Savary, BP 47870, F-21078 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
This work/HITRAN (Cauuet et la, 2000)
Effective Hamiltonian Parameters 10757 Raies attribués, RMS = 3.0×10-4 cm-1 72/219 Paramètres Hamiltonien ajustés en fréquence. 1454 Raies attribués, RMS = 2.4 % 17/30 Paramètres du moment dipolaire ajustés en intensité