Abstract

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

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  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]

2007 (2)

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]

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]

2006 (2)

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]

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]

2005 (2)

2004 (2)

M. Sneep, S. Hannemann, E. J. van Duijn, and W. Ubachs, "Deep-ultraviolet cavity ringdown spectroscopy," Opt. Lett. 29, 1378-1380 (2004).
[CrossRef] [PubMed]

D. S. Moore, "Instrumentation for trace detection of high explosives," Rev. Sci. Instrum. 75, 2499-2512 (2004).
[CrossRef]

2003 (2)

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]

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]

2001 (1)

2000 (4)

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]

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]

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]

G. Berden, R. Peeters, and G. Meijer, "Cavity ring-down spectroscopy: experimental schemes and applications," Int. Rev. Phys. Chem. 19, 565-607 (2000).
[CrossRef]

1998 (2)

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).

J. I. Steinfeld and J. Wormhoudt, "Explosives detection: a challenge for physical chemistry," Annu. Rev. Phys. Chem. 49, 203-232 (1998).
[CrossRef]

1996 (2)

K. K. Lehmann and D. Romanini, "The superposition principle and cavity ring-down spectroscopy," J. Chem. Phys. 105, 10263-10277 (1996).
[CrossRef]

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]

1995 (1)

P. Zalicki and R. N. Zare, "Cavity ring-down spectroscopy for quantitative absorption measurements," J. Chem. Phys. 102, 2708-2717 (1995).
[CrossRef]

1993 (1)

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]

1992 (1)

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]

1988 (1)

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]

1977 (1)

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]

1959 (1)

C. P. Conduit, "Ultraviolet and infrared spectra of some aromatic compounds," J. Chem. Soc. 1959, 3273-3277 (1959).
[CrossRef]

1956 (1)

H. Margenau and G. M. Murphy, The Mathematics of Physics and Chemistry (Van Nostrand, 1956).

Arusi-Parpar, T.

Ashfold, M. N. R.

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).

Bar, I.

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]

Berden, G.

G. Berden, R. Peeters, and G. Meijer, "Cavity ring-down spectroscopy: experimental schemes and applications," Int. Rev. Phys. Chem. 19, 565-607 (2000).
[CrossRef]

Bernstein, E. R.

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]

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]

Brown, S. S.

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]

Cabalo, J.

Clark, A.

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]

Coggiola, M. J.

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]

Conduit, C. P.

C. P. Conduit, "Ultraviolet and infrared spectra of some aromatic compounds," J. Chem. Soc. 1959, 3273-3277 (1959).
[CrossRef]

Dagdigian, P. J.

Fikri, M.

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]

Friedrichs, G.

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]

Greenfield, M.

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]

Guo, Y.

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]

Guo, Y. Q.

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]

Hannemann, S.

Heflinger, D.

Huestis, D. L.

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]

Ibrahim, T. H.

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]

Im, H.-S.

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]

Irwin, A.

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]

Jenings, R.

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]

Kachanov, A. A.

B. A. Paldus and A. A. Kachanov, "An historical overview of cavity-enhanced methods," Can. J. Phys. 83, 975-999 (2005).
[CrossRef]

Koon, K. C.

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]

Lavi, R.

Ledingham, K. W. D.

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]

Lee, Y. T.

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]

Lehmann, K. K.

K. K. Lehmann and D. Romanini, "The superposition principle and cavity ring-down spectroscopy," J. Chem. Phys. 105, 10263-10277 (1996).
[CrossRef]

Lemire, G. W.

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]

Lin, M. C.

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]

Lin, M.-F.

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]

Margenau, H.

H. Margenau and G. M. Murphy, The Mathematics of Physics and Chemistry (Van Nostrand, 1956).

Marshall, A.

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]

Meijer, G.

G. Berden, R. Peeters, and G. Meijer, "Cavity ring-down spectroscopy: experimental schemes and applications," Int. Rev. Phys. Chem. 19, 565-607 (2000).
[CrossRef]

Monts, D. L.

Moore, D. S.

D. S. Moore, "Instrumentation for trace detection of high explosives," Rev. Sci. Instrum. 75, 2499-2512 (2004).
[CrossRef]

Mullen, C.

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]

Murphy, G. M.

H. Margenau and G. M. Murphy, The Mathematics of Physics and Chemistry (Van Nostrand, 1956).

Newman, S. M.

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).

Ni, C.-K.

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]

Orr-Ewing, A. J.

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).

Oser, H.

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]

Paldus, B. A.

B. A. Paldus and A. A. Kachanov, "An historical overview of cavity-enhanced methods," Can. J. Phys. 83, 975-999 (2005).
[CrossRef]

Park, Y.

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]

Peeters, R.

G. Berden, R. Peeters, and G. Meijer, "Cavity ring-down spectroscopy: experimental schemes and applications," Int. Rev. Phys. Chem. 19, 565-607 (2000).
[CrossRef]

Pella, P. A.

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]

Pond, B. V.

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]

Ramos, C.

Ravishankara, A. R.

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]

Rohrer, F.

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]

Romanini, D.

K. K. Lehmann and D. Romanini, "The superposition principle and cavity ring-down spectroscopy," J. Chem. Phys. 105, 10263-10277 (1996).
[CrossRef]

Rosenwaks, S.

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]

Sander, J.

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]

Sausa, R.

Sausa, R. C.

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]

Shu, J.

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]

Simmons, C. M.

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]

Simoneonsson, J. B.

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]

Singh, J. P.

Singhal, R. P.

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]

Sneep, M.

Stark, H.

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]

Steinfeld, J. I.

J. I. Steinfeld and J. Wormhoudt, "Explosives detection: a challenge for physical chemistry," Annu. Rev. Phys. Chem. 49, 203-232 (1998).
[CrossRef]

Stuhl, F.

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]

Temps, F.

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]

Tibere, G. L.

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]

Ubachs, W.

van Duijn, E. J.

Wheeler, M. D.

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).

Wormhoudt, J.

J. I. Steinfeld and J. Wormhoudt, "Explosives detection: a challenge for physical chemistry," Annu. Rev. Phys. Chem. 49, 203-232 (1998).
[CrossRef]

Wu, D.

Xu, S.

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]

Yueh, F. Y.

Zalicki, P.

P. Zalicki and R. N. Zare, "Cavity ring-down spectroscopy for quantitative absorption measurements," J. Chem. Phys. 102, 2708-2717 (1995).
[CrossRef]

Zare, R. N.

P. Zalicki and R. N. Zare, "Cavity ring-down spectroscopy for quantitative absorption measurements," J. Chem. Phys. 102, 2708-2717 (1995).
[CrossRef]

Anal. Chem. (2)

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]

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]

Annu. Rev. Phys. Chem. (1)

J. I. Steinfeld and J. Wormhoudt, "Explosives detection: a challenge for physical chemistry," Annu. Rev. Phys. Chem. 49, 203-232 (1998).
[CrossRef]

Appl. Opt. (4)

Appl. Phys. B (1)

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]

Can. J. Phys. (1)

B. A. Paldus and A. A. Kachanov, "An historical overview of cavity-enhanced methods," Can. J. Phys. 83, 975-999 (2005).
[CrossRef]

Chem. Eng. Commun. (1)

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]

Chem. Phys. Lett. (1)

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]

Int. J. Mass Spectrom. Ion Process. (1)

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]

Int. Rev. Phys. Chem. (1)

G. Berden, R. Peeters, and G. Meijer, "Cavity ring-down spectroscopy: experimental schemes and applications," Int. Rev. Phys. Chem. 19, 565-607 (2000).
[CrossRef]

J. Chem. Phys. (5)

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]

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]

K. K. Lehmann and D. Romanini, "The superposition principle and cavity ring-down spectroscopy," J. Chem. Phys. 105, 10263-10277 (1996).
[CrossRef]

P. Zalicki and R. N. Zare, "Cavity ring-down spectroscopy for quantitative absorption measurements," J. Chem. Phys. 102, 2708-2717 (1995).
[CrossRef]

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]

J. Chem. Soc. (2)

C. P. Conduit, "Ultraviolet and infrared spectra of some aromatic compounds," J. Chem. Soc. 1959, 3273-3277 (1959).
[CrossRef]

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).

J. Chem. Thermodyn. (1)

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]

J. Phys. Chem. A (1)

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]

Opt. Lett. (1)

Phys. Chem. Chem. Phys. (1)

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]

Rev. Sci. Instrum. (1)

D. S. Moore, "Instrumentation for trace detection of high explosives," Rev. Sci. Instrum. 75, 2499-2512 (2004).
[CrossRef]

Other (1)

H. Margenau and G. M. Murphy, The Mathematics of Physics and Chemistry (Van Nostrand, 1956).

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (6)

Fig. 1
Fig. 1

Semilogarithmic plots of the light intensity and 2,6-DNT number density as a function of time, computed using Eqs. (1) and (4), for initial injected light intensities of 5 × 10 3 (top row) and 5 × 10 4   J   cm 2 s 1 (bottom row). The left-hand and right-hand columns of panels pertain to average number densities (l∕L)n of 0.05 and 0.20 times the equilibrium number density of 2,6-DNT at 21 ° C . Other, fixed, parameters are given in the text. The solid lines present the computed light intensities with inclusion of photochemistry, while the dotted–dashed and dotted lines are light intensities computed in the absence of photochemistry [Eq. (1) with constant number density] and an empty cavity, respectively. The computed molecular number densities in the full calculations are plotted as dashed curves. The left-hand axes pertain to the light intensities; the right-hand axes pertain to the molecular number density.

Fig. 2
Fig. 2

(a) Photon decay lifetimes, computed by fits (over 0.1 t 1 μ s after the light pulse) to time-dependent light intensities such as those plotted in Fig. 1, as a function of the initial injected light intensity. Several different average number densities ( l / L ) n , where n is the 2,6-DNT equilibrium number density at 21 ° C , were considered: ( l / L ) = 0.05 (solid curve), 0.20 (dashed curve), and 1 (saturated vapor, dotted–dashed curve). For reference, the assumed empty-cavity lifetime is also plotted (dotted line). (b) The ratio of derived effective absorbances [computed from Eq. (5)] for two pairs of average number densities.

Fig. 3
Fig. 3

Setup for introducing 2,6-DNT vapor into the optical cavity.

Fig. 4
Fig. 4

Linear extrapolation of the photon decay lifetimes measured for 2,6-DNT samples (see Table 1) to zero laser intensity in order to estimate molecular densities for modeling calculations.

Fig. 5
Fig. 5

Photon decay lifetimes determined from fits of time-dependent light intensities computed with the photochemical model presented in Section 2 for the experimental conditions under which the data in Table 1 were taken. An empty-cavity lifetime of 320   ns , as well as average number densities of 2.1 × 10 11 and 4.2 × 10 11 molecules cm−3, were employed in these calculations. For reference, the assumed empty-cavity lifetime is also plotted. The plotted points indicate the light intensities which are consistent with the experimentally determined photon decay lifetimes presented in Table 1, according to calculations with our photochemical model.

Fig. 6
Fig. 6

(a) Computed time-dependent center-line relative molecular concentration for the case of 2.5% depletion by a single laser pulse as affected by diffusion in 1 atm air. The parameters employed in the calculation are given in the text. (b) Time-dependent center-line relative molecular concentration for multiple laser pulses at a repetition rate of 10   Hz , computed with the same parameters as for panel (a).

Tables (1)

Tables Icon

Table 1 CRDS Lifetimes a of 2,6-Dinitrotoluene at 238 nm as a Function of Laser Intensity

Equations (8)

Equations on this page are rendered with MathJax. Learn more.

d I / d t = [ 1 / τ 0 + c n σ ( l / L ) ] I ,
I ( t ) = I 0   exp ( [ 1 / τ 0 + c n σ ( l / L ) ] t ) ,
τ = 1 / [ 1 / τ 0 + c n σ ( l / L ) ] .
d n / d t = n ( t ) σ F ,
α = ( L / c ) ( τ 1 τ 0 1 ) ,
n ( r , t ) = d 2 d 2 + 4 D t   exp ( r 2 d 2 + 4 D t ) ,
I ( ν , z ) = T ( 1 R ) 2 + 4 R sin 2 ( k ( L z ) θ ) ( 1 R ) 2 + 4 R sin 2 ( π ν t r θ ) I i ( ν ) ,
I ( ν , z ) = T ( 1 R ) 2 + 2 R ( 1 R ) 2 + 4 R sin 2 ( π ν t r θ ) I i ( ν ) .

Metrics