Baseline correction of parallel gap of ESR spectra.

[Kob@yashi]

I got this spectra and I have no idea how to correct the gap of right and left parallel line. I tried basecorr function but it didn't work as I wanted. How can I help?

ESR.jpg (57.07 KiB) Viewed 7495 times

[Matt Krzyaniak]

A very simple way is to fit a higher order polynomial to the baseline where there is no spectra. I typically use something like:

Code: Select all

indx =  field<230 | field>350;

[p,S,mu] = polyfit(field(indx),spec(indx),3);

bl = polyval(p,field,S,mu);

plot(field,spec,field,bl)

I will then play around with the limits, indx and the order of the polynomial (last value of polyfit) until I get something that looks reasonably good and doesn't appear to distort the actual spectrum. You might also need to truncate the edges a bit to help the polynomial fit.

[sangita1]

I am also facing the same problem. It will be very helpful if someone can explain how to deal with this type of background.

[sangita1]

I have solved the problem in my case. Actually the background is coming from my substrate on top of which I have deposited my sample. So in that case I have substracted the substrate from my actual sample data like below:

%Imports Data, then the background and subtracts out the background
[B1, spc1, Params1] = eprload('Sample.DTA');
spc2 = spc1;
Params = Params1;
[B3, spc3, Params3] = eprload('Substrate.DTA');
spc = spc2 - spc3;

Hope, I am correct and this will help someone.

Thanks,
Sangita

[Stefan Stoll]

Indeed, this looks like a baseline correction problem that is nicely solved by subtracting the spectrum of an appropriate control sample.