1. First high resolution analysis of the 5 3 band of nitrogen dioxide (NO 2 ) near 1.3 µm Didier Mondelain 1, Agnès Perrin 2, Samir Kassi 1 & Alain Campargue 1 1 Laboratoire Interdisciplinaire de Physique Univ. Grenoble 1 / CNRS, LIPhy UMR 5588, Grenoble, F-38041, France 2 Laboratoire Inter-Universitaire des Systèmes Atmosphériques (LISA), UMR 7583 CNRS et Univ Paris-Est Créteil & Paris Diderot, 94010 Créteil, France

2. NO 2 : some importants points Rotational constants: A~8.0023, B~0.4337 and C~0.4104 cm -1.  1 ~1320 cm -1  2 ~750 cm -1 ;  3 ~1617 cm -1 C-type Coriolis resonance is coupling the (v 1,v 2,v 3 )  (v 1,v 2 +2,v 3 -1) energy levels C-type Coriolis resonance is coupling the (1,0,0)  (0,0,1) energy levels These exists a « electron-spin – rotation » interaction which splits each energy level in two spin-rotation components (considered for all vibrational states) Hyperfine structure (I(N)=1): had to be considered for the (0,0,0) and (0,1,0) vibrational states.

3. NO 2 : already existing studies ( v 1,v 2,v 3 ) (0,0,0) (0,1,0) (1,0,0)(0,2,0)(0,0,1) (0,3,0)(0,1,1) (1,1,0) (1,2,0)(1,0,1) (0,4,0)(0,2,1)(0,0,2) (2,2,0)(2,0,1) (0,2,2) (0,0,3) (1,2,2) (0,8,0) (1,0,3) (4,2,0) (4,0,1) (0,9,0) 0 750 1616. 2355 2063 2906. 3092. 4180 4754 5984 6677 cm -1 C-type Coriolis

4. Last two studies  1 +3 3 band (5984.7 cm -1 ) S. Miljanic et al. Journal of Molecular Spectroscopy 251 (2008) 9–15 (FTS spectra recorded at Créteil, in France).4 1 + 3 band: 6676.9 cm -1 : Perrin et al., JQSRT 111 (2010) 2246–2255 CW-Cavity Ring Down Spectroscopy (Grenoble in France)

5. NO 2 : already existing studies ( v 1,v 2,v 3 ) (0,0,0) (0,1,0) (1,0,0)(0,2,0)(0,0,1) (0,3,0)(0,1,1) (1,1,0) (1,2,0)(1,0,1) (0,4,0)(0,2,1)(0,0,2) (2,2,0)(2,0,1) (0,2,2) (0,0,3) (1,2,2) (0,8,0) (1,0,3) (4,2,0) (4,0,1) (0,9,0) 0 750 1616. 2355 2063 2906. 3092. 4180 4754 5984 6677 cm -1 Higher order resonances C-type Coriolis

6. How can we get informations on the dark states of NO 2 ?????? Delon & Jost. “Laser induced dispersed fluorescence spectra of jet cooled NO 2 : The complete set of vibrational levels up to 10 000 cm -1 & the onset of the X 2 A 1 - ~ 2 B 2 vibronic interaction”, J. Chem. Phys. 95 (8), 15 October 1991

7. Delon & Jost. J. Chem. Phys. 95 (8), 15 October 1991 C-type Coriolis resonances

8. Delon & Jost. J. Chem. Phys. 95 (8), 15 October 1991 C-type Coriolis resonances Higher order resonances

9. The 4 1 + 3 band of NO 2. Perrin, Kassi & Campargue, JQSRT 111, 2246, (2011) Higher order resonances (4,2,0)  (4,0,1) C-type Coriolis resonances

10. Outlook The first high-resolution absorption spectrum of the 5 3 band (0,0,5)-(0,0,0) vibrational transition) of 14 N 16 O 2 in the 7766.070 cm -1 region High sensitivity CW-Cavity Ring Down Spectroscopy between 7674 and 7795 cm-1. (Grenoble’s group) The set of the (0,0,5) spin-rotation energy levels were reproduced within their experimental uncertainty using a theoretical model which takes explicitly into account the Coriolis interactions between the spin rotational levels of the (0,0,5) vibrational state and those of the (0,2,4) dark state The electron spin-rotation resonances within the (0,0,5) and (0,2,4) states were also accounted for. NO higher order Coriolis resonances

11. Experimental details The high-sensitivity absorption spectrum of nitrogen dioxide was recorded at 1.3 µm by CW-Cavity Ring Down spectroscopy (fibered distributed feedback (DFB) spectrometer [2-5]) in Grenoble. Each of the 16 different DFB laser diode has a typical tuning range of about 35 cm -1 by temperature tuning from -10°C to 60°C. Stainless steel CRDS cell (l= 1.4 m, inner diameter F= 10 mm) fitted by a pair of super-mirrors whose reflectivity allows for ring down times ranging from 74 to 166 ms. About 20 to 30 ringdown events were averaged for each spectral data point, and the complete temperature scan of one DFB laser last for about 65 minutes. Noise equivalent absorption  min ~ 1×10 -10 cm -1. Pressure P= 5.0 or 10.0 Torr; Temperature T= 294.3K. [2] Macko, Romanini, Mikhailenko, Naumenko, Kassi, Jenouvrier, et al. J Mol Spectrosc 2004;227:90. [3] Morville, Romanini, Appl. Phys 2004;D78:465. [4] Perevalov, Kassi, Romanini, Perevalov, Tashkun, Campargue. J Mol Spectrosc 2006;238:241. [5] Barbe, De Backer-Barilly, Tyuterev, Kassi, and Campargue J Mol Spectrosc 2011, in press

12. Impurities: water and HF  Overview of the 1.6 µm region

19. C-type Coriolis resonances

20. Hamiltonian matrix

21.  3 band 1007 lines N  47, K a  9 Statistical analysis of the results Number of spin-rotation levels: 531 0 ≤  ≤ 0.002 cm –1 66.7 % 0.002 ≤  ≤ 0.004 cm –1 25.8 % 0.004 ≤  ≤ 0.008 cm –1 7.5 % Standard deviation: 0.13  10 –2 cm –1 Results of the analysis and of the Energy levels calculations

22. W Exp (0,0,1) – (0,2,0)0.01041109[PERR92] (0,1,1) – (0,3,0) 0.010519(11) [PERR94] (0,2,1) – (0,4,0) 0.0108851(79) [PERR96] (0,0,2) – (0,2,1) 0.0099108(25) [PERR96] (1,0,1) – (1,2,0) 0.010651(29) [MAND97] (2,0,1) – (2,2,0) 0.01004(11) [STEP00] (0,0,3) – (0,2,2) 0.010600(53) [STEP00] (1,0,3) – (1,2,2) 0.0108687(76) [MILJ08] (4,0,1)-(4,2,0) 0.012500(53) [PERR10] Average:0.010159(7) (0,0,5)-(0,2,4)0.00688(32) This work C-type Coriolis resonances 1 h C iN y 1 h C iN y + 2 h C {iNy,N z 2 }+…

23. Conclusion The first analysis of the 5 3 band of NO 2 was performed using high resolution cavity ring-down laser spectra recorded at 1.3 µm The Hamiltonian matrix accounts for the (0,0,5)  (0,2,4) C-type Coriolis resonance and for the spin-rotation within (0,0,5) and (0,2,4). No higher order C-type Coriolis was observed, contrary to what was observed for the (4,0,1) and (1,0,3) vibrational states.