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Applied Optics

Applied Optics


  • Editor: James C. Wyant
  • Vol. 46, Iss. 26 — Sep. 10, 2007
  • pp: 6526–6532

Effect of photochemistry on molecular detection by cavity ringdown spectroscopy: case study of an explosive-related compound

Christopher Ramos and Paul J. Dagdigian  »View Author Affiliations

Applied Optics, Vol. 46, Issue 26, pp. 6526-6532 (2007)

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Explosives and explosive-related compounds usually have dissociative excited electronic states. We consider the effect of excited-state dissociation upon an absorption event on the UV cavity ringdown spectroscopy (CRDS) detection of these molecules. A change in the photon decay lifetime with increasing laser energy is demonstrated with vapors of 2,6-dinitrotoluene in the open atmosphere. The magnitude of the effect is modeled with coupled equations describing the time-dependent light intensity and molecular concentration within the cavity. The light intensities required within this model to explain the observed changes in the photon decay lifetimes are consistent with the light intensities expected within the cavity under our experimental conditions. It was also found that the slow diffusion of the molecules in static air can magnify the effect of photochemistry on UV CRDS trace detection of molecules with dissociative excited states.

© 2007 Optical Society of America

OCIS Codes
(280.3420) Remote sensing and sensors : Laser sensors
(300.1030) Spectroscopy : Absorption
(300.6390) Spectroscopy : Spectroscopy, molecular

ToC Category:

Original Manuscript: June 6, 2007
Revised Manuscript: July 17, 2007
Manuscript Accepted: July 24, 2007
Published: September 5, 2007

Christopher Ramos and Paul J. Dagdigian, "Effect of photochemistry on molecular detection by cavity ringdown spectroscopy: case study of an explosive-related compound," Appl. Opt. 46, 6526-6532 (2007)

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  1. M. D. Wheeler, S. M. Newman, A. J. Orr-Ewing, and M. N. R. Ashfold, "Cavity ring-down spectroscopy," J. Chem. Soc. , Faraday Trans. 94, 337-351 (1998).
  2. G. Berden, R. Peeters, and G. Meijer, "Cavity ring-down spectroscopy: experimental schemes and applications," Int. Rev. Phys. Chem. 19, 565-607 (2000). [CrossRef]
  3. B. A. Paldus and A. A. Kachanov, "An historical overview of cavity-enhanced methods," Can. J. Phys. 83, 975-999 (2005). [CrossRef]
  4. M. Sneep, S. Hannemann, E. J. van Duijn, and W. Ubachs, "Deep-ultraviolet cavity ringdown spectroscopy," Opt. Lett. 29, 1378-1380 (2004). [CrossRef] [PubMed]
  5. S. S. Brown, A. R. Ravishankara, and H. Stark, "Simultaneous kinetics and ring-down: rate coefficients from single-cavity loss temporal profiles," J. Phys. Chem. A 104, 7044-7052 (2000). [CrossRef]
  6. Y. Guo, M. Fikri, G. Friedrichs, and F. Temps, "An extended simultaneous kinetics and ringdown model: determination of the rate constant for the reaction SiH2 + O2," Phys. Chem. Chem. Phys. 5, 4622-4630 (2003). [CrossRef]
  7. J. I. Steinfeld and J. Wormhoudt, "Explosives detection: a challenge for physical chemistry," Annu. Rev. Phys. Chem. 49, 203-232 (1998). [CrossRef]
  8. D. S. Moore, "Instrumentation for trace detection of high explosives," Rev. Sci. Instrum. 75, 2499-2512 (2004). [CrossRef]
  9. G. W. Lemire, J. B. Simoneonsson, and R. C. Sausa, "Monitoring of vapor-phase nitro compounds using 226-nm radiation: fragmentation with subsequent NO resonance-enhanced multiphoton ionization detection," Anal. Chem. 65, 529-533 (1993). [CrossRef]
  10. D. Wu, J. P. Singh, F. Y. Yueh, and D. L. Monts, "2,4,6-Trinitrotoluene detection by laser-photofragmentation-laser-induced fluorescence," Appl. Opt. 35, 3998-4003 (1996). [CrossRef] [PubMed]
  11. J. Shu, I. Bar, and S. Rosenwaks, "The use of rovibrationally excited NO photofragments as trace nitrocompounds indicators," Appl. Phys. B 70, 621-625 (2000). [CrossRef]
  12. T. Arusi-Parpar, D. Heflinger, and R. Lavi, "Photodissociation followed by laser-induced fluorescence at atmospheric pressure and 24 °C: a unique scheme for remote detection of explosives," Appl. Opt. 40, 6677-6681 (2001). [CrossRef]
  13. J. Cabalo and R. Sausa, "Trace detection of explosives with low vapor emissions by laser surface photofragmentation-fragment detection spectroscopy with an improved ionization probe," Appl. Opt. 44, 1084-1091 (2005). [CrossRef] [PubMed]
  14. A. Marshall, A. Clark, R. Jenings, K. W. D. Ledingham, J. Sander, and R. P. Singhal, "Laser-induced dissociation, ionization and fragmentation processes in nitroaromatic molecules," Int. J. Mass Spectrom. Ion Process. 116, 143-156 (1992). [CrossRef]
  15. H.-S. Im and E. R. Bernstein, "On the initial steps in the decomposition of energetic materials from excited electronic states," J. Chem. Phys. 113, 7911-7918 (2000). [CrossRef]
  16. M. Greenfield, Y. Q. Guo, and E. R. Bernstein, "Ultrafast photodissociation dynamics of HMX and RDX from their excited electronic states via femtosecond laser pump-probe techniques," Chem. Phys. Lett. 430, 277-281 (2006). [CrossRef]
  17. M.-F. Lin, Y. T. Lee, C.-K. Ni, S. Xu, and M. C. Lin, "Photodissociation dynamics of nitrobenzene and o-nitrobenzene," J. Chem. Phys. 126, 064310 (2007). [CrossRef] [PubMed]
  18. C. Mullen, A. Irwin, B. V. Pond, D. L. Huestis, M. J. Coggiola, and H. Oser, "Detection of explosives and explosive related compounds (ERCs) by single photon laser ionization time of flight mass spectrometry," Anal. Chem. 78, 3807-3814 (2006). [CrossRef] [PubMed]
  19. C. Ramos and P. J. Dagdigian, "Detection of vapors of explosives and explosive-related compounds by ultraviolet cavity ring-down spectroscopy," Appl. Opt. 46, 620-627 (2007). [CrossRef] [PubMed]
  20. P. Zalicki and R. N. Zare, "Cavity ring-down spectroscopy for quantitative absorption measurements," J. Chem. Phys. 102, 2708-2717 (1995). [CrossRef]
  21. F. Rohrer and F. Stuhl, "The 193 (and 248) nm photolysis of HN3: formation and internal energy distributions of the NH(a1?, b1?+, A3?, and c1?) states," J. Chem. Phys. 88, 4788-4799 (1988). [CrossRef]
  22. P. A. Pella, "Measurement of the vapor pressures of TNT, 2.4-DNT, 2.6-DNT, and EGDN," J. Chem. Thermodyn. 9, 301-305 (1977). [CrossRef]
  23. H. Margenau and G. M. Murphy, The Mathematics of Physics and Chemistry (Van Nostrand, 1956).
  24. K. C. Koon, Y. Park, C. M. Simmons, G. L. Tibere, and T. H. Ibrahim, "Molecular diffusion of volatile-liquid vapors into air," Chem. Eng. Commun. 190, 1449-1467 (2003). [CrossRef]
  25. K. K. Lehmann and D. Romanini, "The superposition principle and cavity ring-down spectroscopy," J. Chem. Phys. 105, 10263-10277 (1996). [CrossRef]
  26. C. P. Conduit, "Ultraviolet and infrared spectra of some aromatic compounds," J. Chem. Soc. 1959, 3273-3277 (1959). [CrossRef]

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