The Rotational Spectrum of Chlorine Nitrate (CIONO 2 ): v 6 and the v 5 /v 6 v 9 Dyad

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1 Wright State University CORE Scholar Physics Faculty Publications Physics The Rotational Spectrum of Chlorine Nitrate (CIONO 2 ): v 6 and the v 5 /v 6 v 9 Dyad Zbigniew Kisiel Ewa Bialkowska-Jaworska Rebecca A. H. Butler Douglas T. Petkie Wright State University - Main Campus, doug.petkie@wright.edu Paul Helminger See next page for additional authors Follow this and additional works at: Part of the Physics Commons Repository Citation Kisiel, Z., Bialkowska-Jaworska, E., Butler, R. A., Petkie, D. T., Helminger, P., & De Lucia, F. C. (2008). The Rotational Spectrum of Chlorine Nitrate (CIONO 2 ): v 6 and the v 5 /v 6 v 9 Dyad.. This Presentation is brought to you for free and open access by the Physics at CORE Scholar. It has been accepted for inclusion in Physics Faculty Publications by an authorized administrator of CORE Scholar. For more information, please contact corescholar@

2 Authors Zbigniew Kisiel, Ewa Bialkowska-Jaworska, Rebecca A. H. Butler, Douglas T. Petkie, Paul Helminger, and Frank C. De Lucia This presentation is available at CORE Scholar:

3 62nd OSU International Symposium on Molecular Spectroscopy MI10 The rotational spectrum of chlorine nitrate (ClONO 2 ): ν 6 and the ν 5 / ν 6 ν 9 dyad Zbigniew Kisiel, Ewa Białkowska-Jaworska Institute of Physics, Polish Academy of Sciences Rebecca H Butler Department of Physics, Pittsburgh State University, Douglas T. Petkie, Department of Physics, Wright State University, Paul Helminger, Department of Physics, University of South Alabama, Frank C. De Lucia, Department of Physics, The Ohio State University

4 The chlorine nitrate molecule ( ClONO 2 ) 5 atoms 9 normal modes µ a = 0.72(7) D µ b = 0.24(2) D Takes part in several stratospheric processes: ClO + NO 2 + M ClONO 2 + M ClONO 2 + HCl Cl 2 + HNO 3 ClONO 2 + H 2 O HOCl + HNO 3

5 Previous studies of vibrational satellites in rotational spectrum of ClONO 2 : E /cm 1 Many other states: R.A.H.Butler, PhD Dissertation, Ohio State University (2002) ν 7 ν 9 / 3ν 9 dyad: Butler et al., J.Mol.Spectrosc. 220, 150 (2003) ν 7 / 2ν 9 dyad: Butler et al., J.Mol.Spectrosc. 213, 8 (2003) g.s. and ν 9 : Müller et al., J.Mol.Spectrosc. 161, 363 (1997)

6 This work New, almost continuous GHz spectrum: synthesizer GHz spectrum combined with GHz FASSST spectrum recorded on a cleaner sample. Only GHz missing for technical reasons. AABS package: Assignment and Analysis of Broadband Spectra available from the PROSPE website: Results: 35 ClONO 2 37 ClONO 2 lines σ fit /khz lines σ fit /khz g.s v 9 = v 6 = (v 5 =1)/(v 6 =1,v 9 =1)

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8 Summary of predictions loaded into AABS

9 Visibility of high-k a lines of ν 6 in the FASSST spectrum For J=70 K a =25 E rot = cm -1 intensities E vib = cm -1 E tot = E vib + E rot = cm ClONO 2

10 Data distribution plots for measured ν 6 transitions The obs-calc differences from the final fit are plotted as a function of the lower state quantum numbers with symbol size proportional to the magnitude of the difference. Red circles are for obs-calc > 0.3 MHz

11 Mirror-image perturbations in R-type transitions in the dyad 35 ClONO 2

12 Constants determined for 35ClONO2

13 Coupling constants for the ν 5 /ν 6 ν 9 dyad The (v 5 = 1) state belongs to A representation, while (v 6 =1, v 9 =1) belongs to A representation of the C s symmetry point group for ClONO 2. A A = A, which contains the species of R a and R b. Thus, the two states can couple via Coriolis interaction around both the a and b inertial axes, and the coupling Hamiltonian can be written as: Only the vibrational energy difference and five coupling terms were sufficient to fit all transitions that could be assigned with confidence. 35 ClONO 2 37 ClONO 2

14 Distribution of mixing coefficients and data points 1 P mix o.-c.

15 Perturbation induced hyperfine splitting K a = 3 a R 0,1 transitions in (v 6 =1,v 9 =1) Perturbation maximum is in the 32 3, ,29 transition 35 ClONO 2

16 Interstate transitions The magnitude of hyperfine splitting in the two R-type interstate transitions is comparable to that for the nearby Q-type transition of the ground state 35 ClONO 2

17 The basis for assignment Relative intensities Inertial defect i = I c I a I b (uå 2 ) Vibrational spacing E (cm 1 )

18 Conclusions E /cm 1 Precise constants obtained for two new fundamentals, ν 6 and ν 5, for both 35 Cl and 37 Cl species of ClONO 2 Information obtained on ν 6, ν 9 and ν 6 ν 9 allows confident high-resolution simulation of the ν 6 band in the infrared with its principal hot-band There is sufficient S/N in the FASSST spectrum to expect that several higher fundamentals at cm 1 might be assignable once lower states are sorted out. The triad 4ν 9 / ν 7 2ν 9 / 2ν 7 is next in line