choosing the esfit method (CW, X-band, pepper)

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swayn
Newbie
Posts: 1
Joined: Thu Mar 03, 2016 4:18 am

choosing the esfit method (CW, X-band, pepper)

Post by swayn »

Hello,

it seems this forum is an exclusive chance to communicate with EPR-simulator-profs :) I would to use this possibility and ask for advice..

My task is to simulate a cw-EPR spectrum (X-band) of a powder of silicon nanoparticles (crystalline according to electron diffraction).
The picture is below. The problem is to simulate the double-peak (in the red circle).
Image

I've tried to simulate a complex signal (isotropic one at g=2.0055 + anisotropic from Pb-centers) but after 3 days of simulations my emotion is despair :)
There are too many variables (g-factors, hstrains, weights) to do it manually, but the esfit function does not, it seems, consider this double-peak!

Can anyone help me to choose an appropriate method and target (data as is, integral, etc?) for this task? Maybe some advice abous spin system or something else? :) I'm just a student and a novice in EasySpin, unfortunately for me =(

Code just in case:

Code: Select all

clear

[G,spc]= eprload('file')

Exp.mwFreq = 9.6471;
Exp.nPoints = 1024;
Exp.ModAmp = 0.1; %mT 1 mT = 10 G
Exp.CenterSweep=[344.6 10]; %mT 1 mT = 10 G

Sys1.g = [2.0055];
Sys1.HStrain = [20]; % mHz. 10G=28mHz 
Vary1.g = [0.0005];
Vary1.HStrain = [15];

Sys2.g = [2.009 2.0015];
Sys2.HStrain = [20 10];
Vary2.g = [0.002 0.001];
Vary2.HStrain = [10 6];

Sys1.weight = 1;
Sys2.weight = 1;
Vary1.weight = 0.8;
Vary2.weight = 0.8;

FitOpt.Method = 'genetic fcn';
FitOpt.PopulationSize = 40; % def=20
FitOpt.Scaling = 'lsq';

esfit('pepper',spc,{Sys1,Sys2},{Vary1,Vary2},Exp,[],FitOpt);%multiple components
Attachments
Simul.rar
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Stefan Stoll
EasySpin Creator
Posts: 1073
Joined: Mon Jul 21, 2014 10:11 pm
Location: University of Washington

Re: choosing the esfit method (CW, X-band, pepper)

Post by Stefan Stoll »

This looks like a spectrum with an axial g tensor.
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