What is the significance of (or how do I interpret) the "offset value (Yo)" while I peak-fit spectroscopy data (say FTIR, UV-Vis, XRD etc.) in Origin 8.0 Pro? I understand a more positive offset makes Ymin even smaller but how will that help me analyze a certain peak or help me study the changes in the corresponding bond's nature/properties?
PS: If it needs an example to explain this question, then let's assume I have to analyze amide-bond through FTIR spectroscopy.
Thank you!
In the newer Origin version that I use the y0 value is a constant baseline below the peak. For the nature of the studied bond that's irrelevant, it is just the level of your background noise which depends predominantly on your spectroscopic setup and not your sample.
Programs like Origin to analyze FTIR spectra should be used with caution (even if seemingly everybody does use it without). Absorbance and Lorentzian peak shapes are concepts that are based on approximations which were introduced e.g. by Hendrik Lorentz (A "Lorentzian" or "Lorentz-profile" is nothing but a castrated "Lorentz oscillator" which only works for weak oscillators). If you use them, you should understand them:
Article Quantitative Evaluation of Infrared Absorbance Spectra - Lor...
If you really want to analyze IR-spectra quantitatively, use programs based on "dispersion analysis" like SCOUT/CODE by Wolfgang Theiss or Reffit by Alexey Kuzmenko, or SpIRIT by Konstantin Shportko.
@Dr. Weippert, thankyou.
@Dr. Mayerhöfer, thankyou. May I ask you for your email contact for liaising further
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