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Negative absorption peak in FTIR

  1. Sep 12, 2011 #1
    What does it mean if one found negative absorption in uv-vis absorption graph?
  2. jcsd
  3. Sep 13, 2011 #2

    Jano L.

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    Gold Member

    I have heard this explanation:
    in IR spectroscopy you have to subtract signal due to water and CO2 and if their densities decrease in the course of experiment, your background which you want to subtract may become stronger than the actual background. Then you get negative peaks.
  4. Sep 18, 2011 #3
    Something are exciting over the UV illumination processes.
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