Real-Time Photoacoustic Signal Analysis in a Gas-Phase Spectrophone: A Feasibility Study

Abstract

A digital signal processing (DSP) system has been constructed for the acquisition of intracavity dye laser photoacoustic spectra (ICL-PAS). The DSP system permits observation of the real-time PA pulse, an arrangement which facilitates the adjustment of all spectral acquisition parameters as well as signal processing for noise reduction. Sample spectra of the real-time PA pulse illustrate the improvements possible with Fourier filtering and time-averaging. Spectra of the region of the fifth CH stretching overtone of ethene, benzene, and propane in the gas phase are presented. The system offers significant potential advantages in signal quality, signal processing, and construction cost over the more conventional lock-in amplifier detection method.

Keywords

Digital signal processing Intracavity laser photoacoustic spectroscopy Overtone spectroscopy

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References

Rodin-Bercion

Cavagnat

Lespade

and Maraval

, J. Phys. Chem. 99, 3005 (1995).

Kjaergaard

H. G.

and Henry

B. R

, J. Phys. Chem. 99, 899 (1995).

Davidsson

Gutow

J. H.

and Zare

R. N

, J. Phys. Chem. 94, 4069 (1990).

Quack

, Annu. Rev. Phys. Chem. 41, 839 (1990).

Henry

B. R.

and Sowa

M. G

, Prog. Anal. At. Spectrom. 12, 349 (1989).

Perry

J. W.

Moll

D. J.

Kuppermann

and Zewail

A. H

, J. Chem. Phys. 82, 1195 (1985).

Reddy

K. V.

Heller

D. F.

and Berry

M. J

, J. Chem. Phys. 76, 2814 (1982).

Wong

J. S.

and Moore

C. B

, J. Chem. Phys. 77, 603 (1982).

Henry

B. R.

, Acc. Chem. Res. 20, 429 (1987).

10.

Mecke

, Z. Phys. Chem. B 17, 1 (1932).

11.

Ellis

J. W.

, Phys. Rev. 32, 906 (1928).

12.

Henry

B. R.

Gough

K. M.

and Sowa

M. G

, Int. Rev. Phys. Chem. 5, 133 (1986).

13.

Gough

K. M.

and Henry

B. R

, J. Am. Chem. Soc. 106, 2781 (1984).

14.

Kjaergaard

H. G.

Henry

B. R.

and Tarr

A. W

, J. Chem. Phys. 94, 5844 (1991).

15.

Lehmann

K. K.

and Smith

A. M

, J. Chem. Phys. 93, 6140 (1990).

16.

Tarr

A. W.

Swanton

D. J.

and Henry

B. R

, J. Chem. Phys. 85, 3463 (1986).

17.

Burberry

M. S.

and Albrecht

A. C

, J. Chem. Phys. 71, 4631 (1979).

18.

Lukka

Kauppi

and Halonen

, J. Chem. Phys. 102, 5200 (1995).

19.

Campargue

Permogorov

and Jost

, J. Chem. Phys. 102, 5910 (1995).

20.

Duncan

J. L.

New

C. A.

and Leavitt

, J. Chem. Phys. 102, 4012 (1995).

21.

Hess

, “Principles of Photoacoustic and Photothermal Analysis”, in Photoacoustic, Photothermal and Photochemical Processes in Gases (Springer Verlag, Berlin, 1989), Vol. 46, Chap. 1, p. 1.

22.

Bell

A. G.

, Proc. Am. Assoc. Adv. Sci. 29, 115 (1880); Bell

A. G.

, Philos. Mag. 11, 510 (1881).

23.

Kerr

E. L.

and Atwood

J. G

, Appl. Opt. 7, 915 (1968).

24.

Kreuzer

L. B.

, “The Physics of Signal Generation and Detection”, in Optoacoustic Spectroscopy and Detection, Pao

Y.-H.

, Ed. (Academic Press, New York, 1977), Chap. 1, p. 1.

25.

Dewey

C. F.

Jr. , “Design of Optoacoustic Systems”, in Optoacoustic Spectroscopy and Detection, Pao

Y.-H.

, Ed. (Academic Press, New York, 1977), Chap. 3, p. 47.

26.

Henry

B. R.

Kjaergaard

Niefer

Schattka

B. J.

and Turnbull

D. M

, Can. J. Appl. Spectrosc. 38, 42 (1993).

27.

Camy-Peyret

and Flaud

J.-M

, J. Mol. Spectrosc. 113, 208 (1985).

28.

Veingerov

M. L.

, Dokl. Akad. Nauk. 19, 687 (1939).

29.

Schattka

B. J.

, M.S. Thesis, University of Guelph, Guelph, Ontario, Canada (1993).

30.

Rosencwaig

, “Gas PAS Systems”, in Photoacoustics and Photoacoustic Spectroscopy, Chemical Analysis, Vol. 57 (Wiley–Interscience, New York, 1980), Chap. 4, p. 26.

31.

Smith

A. M.

Jorgensen

U. G.

and Lehman

K. L

, J. Chem. Phys. 87, 5649 (1989).

32.

Wake

D. R.

and Amer

N. M

, Appl. Phys. Lett. 34, 378 (1979).

33.

Schattka

B. J.

Turnbull

D. M.

Kjaergaard

H. G.

and Henry

B. R

, J. Phys. Chem. 99, 6327 (1995).

34.

Gough

K. M.

Henry

B. R.

Schattka

B. J.

and Wildman

T. A

, J. Phys. Chem. 95, 1579 (1991).

35.

Gutow

J. H.

Davidsson

and Zare

R. N

, Chem. Phys. Lett. 185, 120 (1991).

36.

Turnbull

and Henry

B. R

, private communication.