1. TA05 THE ROTATIONAL SPECTRA OF O-17 SUBSTITUTED OXYGEN SINGLET DELTA BRIAN J. DROUIN, HARSHAL GUPTA, SHANSHAN YU, CHARLES E. MILLER, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099 HOLGER S.P. MÜLLER I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, D-50937, Köln, Germany

2. The Big Picture (from TA04) 6/19/2012The Rotational Spectra of 17 O Substituted Oxygen Singlet Delta2 Oxygen has 3 bound states below 3 P dissociation barrier Transitions below UV are magnetic Isotopic bands are observable in Earth atmosphere

3. Previous Work on 1  O 2 O. Leshchishina, et al., J. Quant. Spectrosc. Radiat. Trans., 112, 1257-1265 (2011). ( 17 O IR delta band) S. Kassi, et al., Chem. Phys. Lett. 502, 37-41 (2011). ( 16 O, 18 O IR delta band) RC03 2010 H. Gupta et al. RC03 2010 ( 18 O iso / THz). B.J. Drouin et al. J. Quant. Spectrosc. Radiat. Trans. 111, 1167-1173 (2010). ( 16 O / THz) E.A. Cohen, et al., J. Mol. Spectrosc. 352/353, 283-287 (1995). ( 16 O, 18 O / MW) K. W. Hillig, et al., J. Mol. Spectrosc. 109, 205 (1985). ( 16 O / MW) G. Cazzoli et al., Chem. Phys. Lett. 100, 99-101 (1983). ( 16 O / MW) A. Scalabrin, et al., J. Molec. Spectrosc. 89, 344-351 (1981). ( 16 O / LMR) T. A. Miller, J. Chem. Phys. 54, 330 (1971). ( 16 O / EPR) C. A. Arrington Jr., et al., J. Chem. Phys. 55, 909-914 (1971). ( 17 O / EPR) 6/19/2012The Rotational Spectra of 17 O Substituted Oxygen Singlet Delta3

4. Static Dicharge Cell RC03 2010 Previsously described by H. Gupta et al. RC03 2010 ( 18 O iso / THz). Gas is introduced through a con-flat metal valve that is also ground electrode Two con-flat / quartz transitions on either end of cell Hot electrode is externally connected to power supply and shielded with Teflon THz radiation is passed through angled quartz windows Amorphous quartz attenuates 20% of 500 GHz, 50% of 1000 GHz, 100% 1600 GHz After conditioning, gas pressure stays close to ignition pressure for days 6/19/2012The Rotational Spectra of 17 O Substituted Oxygen Singlet Delta4

5. RC03 2010 Review 24 June 2010H. Gupta, 65th OSU Meeting5 18 O 2 16 O 18 O 16 O 2 Large range in N Modest to deep integration S/N adequate to observe v = 1

6. New Data - 16 O 17 O Despite better throughput at < 500 GHz, best SNR was near 1000 GHz Observed by mixing 90% 17 O 2 with natural sample 50/50 Discharge Voltage 2kV, 40 mA Hyperfine Pattern from I = 5/2 17 O nucleus spin-orbit coupling dominates Boltzmann peak for rotational distribution near 1200 GHz Integration time unlimited Cell contamination and harmonic purity are issues (Blue) prediction from Yu et al. JCP 2012 6/19/2012The Rotational Spectra of 17 O Substituted Oxygen Singlet Delta6

7. New Data - 17 O 2 Observed by discharging 90% 17 O 2 Hyperfine pattern from two equivalent I = 5/2 17 O nuclei (Blue) prediction from Yu et al. JCP 2012 6/19/2012The Rotational Spectra of 17 O Substituted Oxygen Singlet Delta7

8. Present Data Set (pure rotation) 6/19/2012The Rotational Spectra of 17 O Substituted Oxygen Singlet Delta8 a)B.J. Drouin et al. J. Quant. Spectrosc. Radiat. Trans. 111, 1167-1173 (2010). b)K. W. Hillig, et al., J. Mol. Spectrosc. 109, 205 (1985). c) E.A. Cohen, et al., J. Mol. Spectrosc. 352/353, 283-287 (1995).

9. Dunham Analysis 6/19/2012The Rotational Spectra of 17 O Substituted Oxygen Singlet Delta9 1)S. Yu, et al., J. Chem. Phys. (in press) also TA04 6) E.A. Cohen, et al., J. Mol. Spectrosc. 352/353, 283-287 (1995). New!

10. Hyperfine Analysis The Rotational Spectra of 17 O Substituted Oxygen Singlet Delta10 O = O 33 11 34. J.S.M. Harvey, Proc. R. Soc. Lond. A 285, 581-596 (1965). 39. G. Cazzoli, et al., Nuovo Cimento 62 B 243 (1981). 40. H.P. Kelly, Phys. Rev. 180, 55-61 (1969).

11. Born-Oppenheimer Breakdown 6/19/2012The Rotational Spectra of 17 O Substituted Oxygen Singlet Delta11  01 =  01,nonad +  01,ad +  01,Dun 11. Th. Klaus, et al. JMS. 186, 416-421 1997. 23. L. Veseth, Mol. Phys. 36,1255-1260 (1978). 25. H. Christensen, L. Veseth, JMS, 72, 438-444 (1978). 26. Th. Klaus, et al. JMS, 180, 197-206 (1996). 27. W.L. Meerts, et al., Chem. Phys. 22, 319-324 (1977). 28. R. Farrenq, et al. JMS., 149, 375-390 (1991).

12. Acknowledgements 6/19/2012The Rotational Spectra of 17 O Substituted Oxygen Singlet Delta12 John Pearson Tim Crawford NASA - ACLAB / ACLR