Synchrotron-Based High Resolution Spectroscopy of N-Bearing PAHs Sébastien Gruet, Olivier Pirali, Manuel Goubet and P. Bréchignac ISMS /06/2014

Hypothesis : A. Leger, J. L. Puget, A&A 1984, 137, L5. Typical vibrational modes of aromatic compounds: (in µm) at : 3.3, 6.2, 7.7, 8.6, 11.3, 20.8, 27 and 56. (in cm -1 ) at ≈: 3030, 1612, 1298, 1162, 884, 480, 370, and 178. N-Bearing PAHs Peeters et al, 2002, A&A,390, 1089 Rotationally resolved IR data of PAHs in the literature Relatively recent and still scarce One of the first publication: S. Albert et al. Faraday Discuss. 150, (2011) TA11 – Roger Adams Lab 116 – 11 h 35 to 11 h 50 AM Quinoline/Isoquinoline: Z. Kisiel et al. J. Mol. Spectrosc. 217, 115 (2003). Quinoxaline/Quinazoline: D. McNaughton, J. Chem. Phys. 124, (2011) 2

3 Experimental device Room temperature long pathlength cell (150m) Bruker IFS 125 Resolution: cm -1 ≈ 30MHz Bruker IFS 125 Resolution: cm -1 ≈ 30MHz

4 Resolution: 0.5cm

5 Resolution: cm -1 Butterfly Mode Drumhead Mode C-H oop Mode

6 Effective Hamiltonian for asymmetric top molecules : Study of the out of plane vibrational modes : Selection rules for c-type transitions : Butterfly mode at ≈ 170 cm -1 c a b c

7

Molecules IsoquinolineQuinolineQuinoxalineQuinazoline[1,5]-naphthyridine Parametersν 41 ν 37 ν 45 ν 41 ν 28 ν 27 ν 38 ν 22 ν 18 Band Center cm -1 /MHz (14)/ (41) (20)/ (60) (17)/ (45) (12)/ (37) (23)/ (71) (7)/ (21) (17)/ (45) (12)/ (37) (14)/ (41) A /MHz (57) (99) (10) (49) (10) (17) (69) (22) (22) B /MHz (25) (90) (10) (21) (21) (11) (61) (52) (47) C /MHz (36) (13) (11) (31) (32) (16) (85) (52) (40) Δ J /kHz (57) (39) (70) (78) (53) (11) (19) (56) (60) Δ K /kHz (33) (44) (12) (32) (89) (67) (62) (49) Δ JK /kHz (26) (19) (78) (28) (38) (58) (70) (37) (28) δ J /kHz * (62) * * * δ K /kHz * (76) * * * N of lines IR RMS cm cm cm cm cm cm cm cm cm -1 J” min /J” max 14/9917/8715/9415/9912/9915/8317/999/9911/91 Ka” min /Ka” max 14/6417/4314/5014/6012/4814/4117/529/ rovibrational bands analyzed for these 5 molecules. Analysis of 3 other bands in progress. Determination of the GS constants of the [1,5]-napthyridine.

9 Anharmonic DFT calculation at the B97-1/cc-pVTZ//ANO-DZP level Accurate calculated rotational parameters More details about calculations: M. Goubet, O. Pirali, J. Chem Phys. 140, (2014) Useful tool to begin the GSCD analysis by LWW diagram Quinoxaline ModeGS 27 ParametersCalculatedExperimentalDeviationCalculatedExperimentalDeviation A /MHz B /MHz C /MHz Corrected Calculated Values ExperimentalDeviation the B97-1/cc-pVTZ//ANO-DZP level Anharmonic DFT calculation at the B97-1/cc-pVTZ//ANO-DZP level

MoleculesQuinazolineQuinoline[1,5]-naphthyridine ModesGSν 38 GSν 45 ν 41 GSν 22 ν 18 Experimental MoleculesQuinazolineQuinoline[1,5]-naphthyridine ModesGSν 38 GSν 45 ν 41 GSν 22 ν 18 Experimental MoleculesQuinazolineQuinoline[1,5]-naphthyridine ModesGSν 38 GSν 45 ν 41 GSν 22 ν 18 Calculated Experimental MoleculesQuinazolineQuinoline[1,5]-naphthyridine ModesGSν 38 GSν 45 ν 41 GSν 22 ν 18 Calculated Experimental Deviation Check the reliability of our fitted rotational constants Contribution of the out of plane low frequency modes (GS) Correlation with the amplitude of the deformation motions (ES)

11

Pure rotational transitions in the ES.  Collaboration: LPCA Dunkerque (Fr) & PhLAM Laboratory (Fr) & IP PAS (Pl) 12 Important database of rotational information in the IR  Simulation at different resolution and at low temperature Study of larger molecules : Jet-AILES Experiment (IPR, LADIR, PhLAM, SOLEIL) FA09 – Roger Adams Lab 116 – 11 h 01 to 11 h 16 AM