Skip to main content
Log in

Time-resolved spectroscopic study of photofragment fluorescence in methane/air mixtures and its diagnostic implications

  • Published:
Applied Physics B Aims and scope Submit manuscript

Abstract

In this work 80-picosecond laser pulses of 266-nm wavelength with intensities up to (2.0 ± 0.5) × 1011 W/cm2 were used for fragmentation of methane/air gas mixtures at ambient pressure and temperature. Emission spectra are, for the first time, studied with ultrahigh temporal resolution using a streak camera. Fluorescence spectra from CH(A2Δ–X2Π, B2Σ–X2Π, C2Σ+–X2Π), CN(B2Σ+–X2Σ+, Δv = 0 and Δv = ±1), NH(A3Π–X3Σ), OH(A2Σ+–X2Π) and N2 +(B2Σ +u –X2Σ +g ) were recorded and analyzed. By fitting simulated spectra to high-resolution experimental spectra, rotational and vibrational temperatures are estimated, showing that CH(C), CN(B), NH(A), and OH(A) are formed in highly excited vibrational and rotational states. The fluorescence signal dependencies on laser intensity and CH4/air equivalence ratio were investigated as well as the fluorescence lifetimes. All fragments observed are formed within 200 ps after the arrival of the laser pulse and their fluorescence lifetimes are shorter than 1 ns, except for CN(B–X) Δv = 0 whose lifetime is 2.0 ns. The CN(B–X) Δv = 0 fluorescence was studied temporally under high spectral resolution, and it was found that the vibrational levels are not populated simultaneously, but with a rate that decreases with increasing vibrational quantum number. This observation indicates that the rate of the chemical reaction that forms the CN(B) fragments is decreasing with increasing vibrational state of the product. The results provide vital information for the application of laser diagnostic techniques based on strong UV excitation, as they show that such methods might not be entirely non-intrusive and suffering from spectral interferences, unless the laser intensity is kept sufficiently low. Finally, equivalence ratios were determined from “unknown” spectra using multivariate analysis, showing a good agreement with theoretical compositions with an error of 4 %. The method is expected to be a useful diagnostic tool for measurements of local equivalence ratios in for example combustion environments.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9

Similar content being viewed by others

References

  1. E. Schreiber, Ultrafast Photodissociation (Springer, Berlin, 1998)

    Google Scholar 

  2. P. Hering, C. Cornaggia, Phys. Rev. A 57, 4572–4580 (1998)

    Article  ADS  Google Scholar 

  3. D. Mathur, C. P. Safvan, G. Ravindra Kumar, and M. Krishnamurthy, Phys. Rev. A 50, R7–R9 (1994)

    Article  ADS  Google Scholar 

  4. M. Sharifi, F. Kong, S.L. Chin, H. Mineo, Y. Dyakov, A.M. Mebel, S.D. Chao, M. Hayashi, S.H. Lin, J. Chem. Phys. 111, 9405–9416 (2007)

    Article  Google Scholar 

  5. D. Mathur, F.A. Rajgara, J. Chem. Phys. 120, 5616–5623 (2004)

    Article  ADS  Google Scholar 

  6. S. Wang, X. Tang, L. Gao, M.E. Elshakre, F. Kong, J. Phys. Chem. A 107, 6123–6129 (2003)

    Article  Google Scholar 

  7. C. Wu, H. Ren, T. Liu, R. Ma, H. Yang, H. Jiang, Q. Gong, J. Phys. B: Atm. Mol. Opt. Phys. 35, 2575 (2002)

    Article  ADS  Google Scholar 

  8. J.S. Levine, The Photochemistry of Atmospheres (Academic, New York, 1985)

    Google Scholar 

  9. R.P. Wayne, Chemistry of Atmospheres (Oxford University, New York, 1991)

    Google Scholar 

  10. H. Rodhe, Science 248, 1217–1219 (1990)

    Article  ADS  Google Scholar 

  11. C. Johnson, J. Henshaw, G. McLnnes, Nature 355, 69–71 (1992)

    Article  ADS  Google Scholar 

  12. H.O.W.M. Jackson, Photodissociation Dynamics of Small Molecules in Advances in Photochemistry, vol. 13 (Wiley, Colorado, 1986)

    Google Scholar 

  13. R. Schinke, Photodissociation Dynamics (Cambridge University Press, Cambridge, 1993)

    Book  Google Scholar 

  14. R. Schinke, in Encyclopedia of Computational Chemistry (John Wiley & Sons, Ltd, 2002)

  15. F. Kong, Q. Luo, H. Xu, M. Sharifi, D. Song, S.L. Chin, J. Chem. Phys. 125, 133320 (2006)

    Article  ADS  Google Scholar 

  16. H.L. Xu, J.F. Daigle, Q. Luo, S.L. Chin, Appl. Phys. B. 82, 655–658 (2006)

    Article  ADS  Google Scholar 

  17. H.L. Xu, Y. Kamali, C. Marceau, P.T. Simard, W. Liu, J. Bernhardt, G. Méjean, P. Mathieu, G. Roy, J.-R. Simard, S.L. Chin, Appl. Phys. Lett. 90, 101106 (2007)

    Article  ADS  Google Scholar 

  18. M. Kotzagianni, S. Couris, Appl. Phys. Lett. 100, 264104 (2012)

    Article  ADS  Google Scholar 

  19. H.-L. Li, H.-L. Xu, B.-S. Yang, Q.-D. Chen, T. Zhang, H.-B. Sun, Opt. Lett. 38, 1250–1252 (2013)

    Article  ADS  Google Scholar 

  20. M. Kotzagianni, S. Couris, Chem. Phys. Lett. 561–562, 36–41 (2013)

    Article  Google Scholar 

  21. W. Chu, H. Li, J. Ni, B. Zeng, J. Yao, H. Zhang, G. Li, C. Jing, H. Xie, H. Xu, K. Yamanouchi, Y. Cheng, Appl. Phys. Lett. 104, 091106 (2014)

    Article  ADS  Google Scholar 

  22. D.W. Hahn, N. Omenetto, Appl. Spectrosc. 64, 335A–366A (2010)

    Article  ADS  Google Scholar 

  23. D.W. Hahn, N. Omenetto, Appl. Spectrosc. 66, 347–419 (2012)

    Article  ADS  Google Scholar 

  24. S. L. Chin, Femtosecond Laser Filamentation, Springer series on Atomic, Optical, and Plasma Physics (Springer Sci. Business Media, New York, 2010), Vol. 55

  25. J. Luque, D. R. Crosley, in LIFBASE: Database and spectral simulation (version 1.5) (SRI International Report MP 99-009, 1999)

  26. C. M. Western, in PGOPHER, A program for simulating rotational structure ((University of Bristol, Bristol, UK). http://pgopher.chm.bris.ac.uk, 2010)

  27. R.S. Ram, P.F. Bernath, J. Mol. Spectrosc. 260, 115–119 (2010)

    Article  ADS  Google Scholar 

  28. S. Yuan, T. Wang, P. Lu, S. Leang Chin, and H. Zeng, 104, 091113 (2014)

  29. K. Liu, D. Song, F. Kong, Laser Phys. 19, 1640–1650 (2009)

    Article  ADS  Google Scholar 

  30. A.J.R. Heck, R.N. Zare, D.W. Chandler, J. Chem. Phys. 104, 4019–4030 (1996)

    Article  ADS  Google Scholar 

  31. A. Azarm, H. Xu, Y. Kamali, J. Bernhardt, D. Song, A. Xia, Y. Teranishi, S. Lin, F. Kong, S. Chin, J. Phys. B: At. Mol. Opt. Phys. 41, 225601 (2008)

    Article  ADS  Google Scholar 

  32. S. G. Lias, J. E. Bartmess, J. F. Liebman, J. L. Holmes, R. D. Levin, and W. G. Mallard, (NIST Standard Reference Database Number 69, http://webbook.nist.gov, retrieved November 29, 2014)

  33. M. Kato, K. Kameta, T. Odagiri, N. Kouchi, Y. Hatano, J. Phys. B. 35, 4383 (2002)

    Article  ADS  Google Scholar 

  34. M. Tamura, P.A. Berg, J.E. Harrington, J. Luque, J.B. Jeffries, G.P. Smith, D.R. Crosley, Combust. Flame 114, 502–514 (1998)

    Article  Google Scholar 

  35. N.L. Garland, D.R. Crosley, J. Chem. Phys. 90, 3566–3573 (1989)

    Article  ADS  Google Scholar 

  36. A. Hofzumahaus, F. Stuhl, J. Chem. Phys. 82, 3152–3159 (1985)

    Article  ADS  Google Scholar 

  37. R. Schwarzwald, P. Monkhouse, J. Wolfrum, Symp. (Int.) Combust. 22, 1413–1420 (1989)

    Article  Google Scholar 

  38. A.C. Eckbreth, Laser diagnostics for combustion temperature and species (Gordon and Breach Publishers, Combustion science and technology book series, 1996)

    Book  Google Scholar 

  39. K. Kohse-Höinghaus, J.B. Jeffries, Applied Combustion Diagnostics (Combustion, An international series. Taylor and Francis, 2002)

    Google Scholar 

  40. O. Johansson, J. Bood, M. Aldén, U. Lindblad 62, 66–72 (2008)

    Google Scholar 

  41. O. Johansson, J. Bood, B. Li, A. Ehn, Z.S. Li, Z.W. Sun, M. Jonsson, A.A. Konnov, M. Aldén 158, 1908–1919 (2011)

    Google Scholar 

  42. M. Jonsson, A. Ehn, M. Christensen, M. Aldén, J. Bood, Appl. Phys. B. 115, 35–43 (2014)

    Article  ADS  Google Scholar 

  43. H. Mark, and J. Workman Jr, Chemometrics in spectroscopy (Academic Press, 2010)

Download references

Acknowledgments

The present work has been financed by DALDECS, an Advanced Grant from the European Research Council (ERC), the Knut and Alice Wallenberg Foundation, and the Swedish Energy Agency (Energimyndigheten) through the Centre for Combustion Science and Technology (CECOST).

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Malin Jonsson.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary material 1 (PDF 91 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Jonsson, M., Borggren, J., Aldén, M. et al. Time-resolved spectroscopic study of photofragment fluorescence in methane/air mixtures and its diagnostic implications. Appl. Phys. B 120, 587–599 (2015). https://doi.org/10.1007/s00340-015-6170-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00340-015-6170-5

Keywords

Navigation