| T O P I C R E V I E W |
| hergen |
Posted - 08/02/2022 : 5:18:49 PM
I want to fit an optical absorption spectrum (intensity vs. wavelength). Multiple chemicals (each with its own characteristic absorption spectrum) but unknown concentrations, are contributing to the measured spectrum. I’m trying to determine the concentrations of the individual chemicals.
In the simplest case, I have the reference spectra of two chemicals and the measured spectrum:
Col(A): Wavelength
Col(B): Reference spectrum for chemical 1.
Col(C): Reference spectrum for chemical 2.
Col(D): Measured spectrum.
Each column could contain 1000s of data point.
Col(D) = concentration 1 * Col(B) + concentration 2 * Col(C)
How can I do that in OriginPro?
Thank you.
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| 3 L A T E S T R E P L I E S (Newest First) |
| hergen |
Posted - 08/03/2022 : 1:29:25 PM
Thank you. |
| Echo_Chu |
Posted - 08/03/2022 : 03:32:42 AM
The app should work as you want
https://www.originlab.com/fileExchange/details.aspx?fid=406
Echo
OriginLab Technical Support |
| aplotnikov |
Posted - 08/03/2022 : 03:23:22 AM
Use reference spectra as X-columns (X1, X2) and the measured spectra as Y (in particular - Y2).
Create an NL fit function:
y=c1*x1+c2*x2 (I would suggest to add background as well: y=c1*x1+c2*x2+y0), where x1 and x2 - independent variables and c1,c2(,y0) - parameters to fit.
Now if you select all three columns and start non-linear fitting session for the selected data with the created function the dataset names should be determined automatically. Set boundaries for parameters, etc. if necessary. Start fitting. |
