Title: A DISCUSSION ABOUT THE SIGNIFICANCE OF ABSORBANCE AND SAMPLE OPTICAL THICKNESS IN CONVENTIONAL ABSORPTION SPECTROMETRY AND WAVELENGTH MODULATED LASER ABSORPTION SPECTROMETRY Author
Submitted to: Spectrochimica Acta
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 15, 2003
Publication Date: January 15, 2004
Citation: Harnly, J.M. 2004. A discussion about the significance of absorbance and sample optical thickness in conventional absorption spectrometry and wavelength modulated laser absorption spectrometry. Spectrochimica Acta, Part B. 59:389-392. Interpretive Summary: This short communication appeared in the Views and Criticisms section of Spectrochimica Acta, Part B. I was asked to review a manuscript for the journal and I recommended rejection. The journal decided that they would not make an editorial decision and, instead, would publish the paper, my criticisms, and the authors rebuttal together. Thus, they requested that I write a short communication with my criticisms. The paper in question describes a new atomic absorption instrument that uses a diode laser as the light source. The intensity measurements were made at a high rate using a lock-in amplifier (synchronous detection). The authors contended that it was not possible to convert these measurements into units of absorbance, the IUPAC standard for atomic absorption spectrometry. My criticism was that the technology was available for computing absorbance. I pointed out that it had been done for years by a number of researchers using continuum source AAS with wavelength modulation and I cited the appropriate papers. I also pointed out that it was not possible to accurately asses the performance of the new instrument unless the authors adhered to IUPAC standards. This paper will hopefully discourage development of a fundamentally unsupported measurement system and encourage conformance to IUPAC standards. This will eliminate confusion in the spectroscopic community.
Technical Abstract: There is no technical abstract. This paper was a short communication of an alternative viewpoint that appeared with the original research paper in question and a rebuttal letter by the authors of the paper.