A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 New analysis of the 3 & 4 bands of HNO 3 by high resolution Fourier transform spectroscopy in the 7.6 µm region PRELIMINARY RESULTS Agnés Perrin J.Orphal, J.-M.Flaud, S.Miljanic, Laboratoire Interuniversitaire des Systémes Atmosphériques (LISA), CNRS, Université Paris XII, Créteil S. Klee, G. C. Mellau, Justus-Liebig – Universität, Gießen, Germany; A. Goldman, Department of Physics, University of Denver,, USA.

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 HNO 3 in HITRAN MW 9 { 5,2 9 ) { 4, 3 } cm cm , 896cm , 1326cm cm -1 Far-IR 22µm 11µm 7.6µm 5.8µm ACE (Atmospheric Chemistry Experiment (FTS on the SCISAT-1 canadian satellite P.Bernath, Intensities MIPAS on ENVISAT

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 MW & 9 { 5,2 9 ) { 4, 3 } cm cm , 896cm , 1326cm cm -1 Far-IR 22µm 11µm 7.6µm 5.8µm Intensities MIPAS : up to now HNO 3 is measured only in the 11 µm region (micro-windows) Updates of HNO 3 parameters for the MIPAS database (now in HITRAN) were partially successful Improved line positions at 11 µm ( 5 and 2 9 bands): Coherence in the HNO 3 line intensities for the 11µm  7.6 µm  5.8 µm Perrin, Orphal, Flaud, Klee, Mellau, Mäder, Walbrodt & Winnewisser, J. Mol. Spect 228 (2004) Flaud, Brizzi, Carlotti, Perrin & Ridolfi Atmos. Chem. Phys., 6, 1–12, Goal for MIPAS: to extend the range of the micro-windows and/or to take use of other spectral regions

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 Comparison of observed and simulated MIPAS spectra (11µm) for an altitude of 24km Old databaseNew database 2 9 Q branch Perrin, Orphal, Flaud, Klee, Mellau, Mäder, Walbrodt & Winnewisser, J. Mol. Spect 228 (2004) Flaud, Brizzi, Carlotti, Perrin & Ridolfi Atmos. Chem. Phys., 6, 1–12, 2006.

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 HNO 3 in HITRAN MW & 9 { 5,2 9 ) { 4, 3 } cm cm , 896cm , 1326cm cm -1 Far-IR 22µm 11µm 7.6µm 5.8µm Intensities

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 Status of the 3 & 4 bands (7.5µm) …still unsatisfactory !!!!!!!!!. 3 Q branch

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 Goldman & Rinsland, JQSRT 48 (1992) --- Obs Laboratory Denver __ Calc Strong desagrement between the Obs and Calc spectra !! NOT suitable for atmospheric retrievals HNO 7.6 µm in HITRAN Q - branch A.Perrin, O.Lado-Bordowski, & A. Valentin, Mol. Phys. 67, 249 ( 1989 ).

A.Perrin: Ohio-State 62th Molecular Symposium, June µm( 3 & 4 bands) in 1989… A.Perrin, O.Lado-Bordowski, & A. Valentin, Mol. Phys. 67, 249 (1989). Only a partial analysis of the 3 and 4 bands was performed The model did not account from the resonances involving the dark bands Line position calculation: the calculated energy levels were replaced by the observed ones (when existing…!!!) 1303 cm cm WAnh +C 3131 W

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 This work FTS spectra recorded at Giessen (Germany) Bruker- 120HR  High resolution, different experimental conditions (temperatures, path-lengths, pressure…) FTS spectra recorded at Denver University (USA) for the hot band New analysis of the spectra New theoretical model

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 Two bright bands ( 3 & 4 ) four dark interacting bands.. (3 9, 2 6, & ) Information on 3 9 and dark bands …from the analysis of the and hot bands It is necessary to account for the torsional large amplitude effects in µm( 3 & 4 bands) in 2007

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 W= Watson hamiltonian (for the v  v diagonal operators) v  v’ off diagonal operators (same symmetry) A’  A’ or A’’  A’’ C-type Coriolis (and/or) F: Fermi; Anh: Anharmonic 9 3  9 3 diagonal block only Torsion: large amplitude torsion IAM like treatment.v  v’ off diagonal operators (different symmetry) A’  A’’ A-type Coriolis (and/or) B-type Coriolis Symmetry considerations: vibrational states with (v 8 +v 9 )=even A’ symmetry (v 8 +v 9 )=odd A’’ symmetry Theoretical model Reasonable agreements between the observed and calculated energy levels up to J=35, but still remaining problems above

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 Hamiltonian matrix Informations on the: * dark state from the Q branch of the hot band

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 Position of the dark band (center at cm -1 ) … from the hot band

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 Hamiltonian matrix Informations on the: 9 3 dark state from the hot band Large amplitude OH torsion

A.Perrin: Ohio-State 62th Molecular Symposium, June torsion OH/NO 2 (3 9 at cm -1 ) H H O B O O O N O N z x x 9 torsion of OH /NO 2  large amplitude y y z Splitting of ~ 0.06 cm -1 in 9 3

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007

Transfert of the torsional splitting via the 4  3 9 interaction

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 Hamiltonian matrix

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 Vibrational Energies: E 99 =889.3 cm -1 E 5 = cm -1 E 9 = 458 cm -1.Band centers 99 =896.4 cm -1 5 = cm -1 Vibrational Energies: E 59 = cm -1 E 999 = cm -1.Band centers 59 = cm = cm -1 F 0 =8.53 cm -1 $ F 0 =8.53*√3 cm -1  5  2 9 Fermi resonance   3 9 Fermi resonance 11µm region 7.6 µm region $ Petkie, Goyette, Helminger, Pickett, De Lucia. J.Mol Spectr. 208 (2001) Perrin, Orphal, Flaud, Klee, Mellau, Mäder, Walbrodt and Winnewisser, J. Mol. Spect 228 (2004)

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 The 2 6 band

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 R branch of the 4 band

A.Perrin: Ohio-State 62th Molecular Symposium, June band: Q branch GEISA

A.Perrin: Ohio-State 62th Molecular Symposium, June band: Q branch GEISA

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007

Prospective To continue the analyses of the 3 & 4 bands at 7.6 µm From this study at 7.6 µm (which involves, among others, the vibrational dark state……try to get information for the hot band (at 11 µm)

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 CONCLUSION A new (on going) study of the 3 et 4 bands of HNO 3 was performed It is necessary to account for resonances involving the 3 9, 2 6 et & dark bands. Financial support from the French program « LEFE- CHAT » (Les Enveloppes Fluides et l'Environnement, Chimie Atmosphérique) of CNRS-INSU is gratefully acknowledged.

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 J.-M. Flaud, G. Brizzi, M. Carlotti, A. Perrin, and M. Ridolfi Atmos. Chem. Phys., 6, 5037–5048, 2006 OLD NEW

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 Perrin et al. J.Mol. Spect or GEISA

A.Perrin: Ohio-State 62th Molecular Symposium, June 2007 Michelson Interferometer for Passive Atmospheric Sounding 11µm 5, µm 3, 4 5.8µm  2 (26km) HNO 3 is measured in « real time » using an « operational code » which use « limited » microwindows (11µm for HNO 3 ) Futur projects: to use more of the informations included in MIPAS spectra & extend the range of the microwindows MIPAS is an high resolution IR FTS spectrometer onboard the ENVISAT satellite since march 2002

A.Perrin: Ohio-State 62th Molecular Symposium, June v=0 (ground). v= extremely weak band. v= weak band 9