OSA's Digital Library

Journal of the Optical Society of America

Journal of the Optical Society of America

  • Vol. 42, Iss. 1 — Jan. 1, 1952
  • pp: 1–5

Experimental Determination of Absolute ƒ-Values for Methane


JOSA, Vol. 42, Issue 1, pp. 1-5 (1952)

View Full Text Article

Acrobat PDF (687 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



The absolute ƒ-values of rotational lines in the positive and negative branches of the 2ν3 overtone band of CH4 have been derived from absorption measurements in the laboratory by two independent methods. The first method involves the use of the curve of growth and requires the observation of weak lines for which the total absorption is independent of the damping constant. In the second method the lines are broadened artificially, by the introduction of about 3 atmos of air, to half-widths that are about five times the slit width. The ƒ-values are then determined by integration of the logarithm of the percentage absorption over the line profile. On the average, the ƒ-values obtained by the two methods agree within 10 percent.

LEO GOLDBERG, ORREN C. MOHLER, and RUSSELL E. DONOVAN, "Experimental Determination of Absolute ƒ-Values for Methane," J. Opt. Soc. Am. 42, 1-5 (1952)

Sort:  Author  |  Journal  |  Reset


  1. Robert R. McMath and Orren C. Mohler, J. Opt. Soc. Am. 39, 903 (1949).
  2. E. B. Wilson, Jr., and A. J. Wells, J. Chem. Phys. 14, 578 (1946).
  3. D. M. Dennison, Phys. Rev. 31, 503 (1928).
  4. A. Unsöld, Pysik der Sternatmosphären (Verlag. Julius Springer, Berlin, 1938), p. 165.
  5. Actually, the collisional damping may be expected to increase slightly with excitation potential, since, owing to the interaction between rotation and vibration, the internuclear distance and therefore the target area for collision increases with increasing rotation. But the effect is negligibly small.
  6. G. Herzberg, Infra Red and Raman Spectra (D. van Nostrand Company, Inc., New York, 1945), p. 451.
  7. See reference 6, p. 506.
  8. W. H. J. Childs and H. A. Jahn, Proc. Roy. Soc. (London) A169, 451 (1939).

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited