Investigating the Beer-Lambert Law in a Cavity-Enhanced Spectroscopic Method

ORAL

Abstract

Incoherent broad-band cavity-enhanced absorption spectroscopy has been used for high sensitivity measurements of weak transitions in solution. When the method has been used to make Beer-Lambert plots, the linear range has been observed to be significantly truncated and the dynamic range extended. This is preventing the use of this method for accurate quantitative measurements of the absorbance of weak signals in solution. We hypothesize that the behavior observed in the Beer-Lambert plots can be explained by accounting for losses per pass due to the cavity enhancement. Experimentation to create the Beer-Lambert plots described has been done varying the concentration of weakly absorbing analytes, such as methanol and toluene in the range of red light, as well as varying the size of the cuvette, effectively varying the path length of light traveling through the liquid-phase sample. The results of the experimentation have been compared to the predicted trend of the Lambert-Beer law.

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Authors

  • Zane Thornburg

    The College of Wooster

  • Rudrakant Sollapur

    Miami University, The College of Wooster, University of Dayton, Ohio University and Argonne National Laboratory, Argonne National Laboratory, J. Stefen Inst., Slovenia, Ohio University, Institute of Physics, University of Belgrade, The University of Akron, Faculty of Physics, University of Belgrade, Institute for Multidisciplinary Research, University of Belgrade, Faculty of Sciences, University of Novi Sad, Bowling Green State University, Australian National University, Benet lab, Department of Physics and Electro-Optics Program University of Dayton, Dayton, OH 45469, Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ, Department of Physics, Arizona State University, Tempe, AZ, Electro-Optics Program, University of Dayton, Dayton, OH 45469, Department of Physics and Astronomy, Youngstown State University, University of Memphis, TN, Union College Barbourville, KY, Air Force Research Laboratory, Materials and Manufacturing Directorate, WPAFB, OH, Arizona State University, Materials and Manufacturing Directorate, Air Force Research Laboratory, WPAFB, OH 45433, Materials and Manufacturing Directorate, Wright-Patterson AFB, OH, Case Western Reserve University, Department of Electrical Engineering and Computer Science, Cleveland, OH, Air Force Research Lab, Materials and Manufacturing Directorate, WPAFB, OH, Ohio Northern Univ, University of Notre Dame, Miami Univ, Leibniz Institute of Photonic Technology e.V.; and Otto Schott Institute of Material Research, Abbe Center of Photonics, Leibniz Institute of Photonic Technology e.V., Institute of Optics and Quantum Electronics, Abbe Center of Photonics, Friedrich Schiller University; and Helmholtz Institute Jena, Institute of Optics and Quantum Electronics, Abbe Center of Photonics, Friedrich Schiller University

  • Rudrakant Sollapur

    Miami University, The College of Wooster, University of Dayton, Ohio University and Argonne National Laboratory, Argonne National Laboratory, J. Stefen Inst., Slovenia, Ohio University, Institute of Physics, University of Belgrade, The University of Akron, Faculty of Physics, University of Belgrade, Institute for Multidisciplinary Research, University of Belgrade, Faculty of Sciences, University of Novi Sad, Bowling Green State University, Australian National University, Benet lab, Department of Physics and Electro-Optics Program University of Dayton, Dayton, OH 45469, Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ, Department of Physics, Arizona State University, Tempe, AZ, Electro-Optics Program, University of Dayton, Dayton, OH 45469, Department of Physics and Astronomy, Youngstown State University, University of Memphis, TN, Union College Barbourville, KY, Air Force Research Laboratory, Materials and Manufacturing Directorate, WPAFB, OH, Arizona State University, Materials and Manufacturing Directorate, Air Force Research Laboratory, WPAFB, OH 45433, Materials and Manufacturing Directorate, Wright-Patterson AFB, OH, Case Western Reserve University, Department of Electrical Engineering and Computer Science, Cleveland, OH, Air Force Research Lab, Materials and Manufacturing Directorate, WPAFB, OH, Ohio Northern Univ, University of Notre Dame, Miami Univ, Leibniz Institute of Photonic Technology e.V.; and Otto Schott Institute of Material Research, Abbe Center of Photonics, Leibniz Institute of Photonic Technology e.V., Institute of Optics and Quantum Electronics, Abbe Center of Photonics, Friedrich Schiller University; and Helmholtz Institute Jena, Institute of Optics and Quantum Electronics, Abbe Center of Photonics, Friedrich Schiller University