Hello
I am trying to model EPR spectrum of a 3 spins system Sys.S=[1, 1/2,1] . I have ZFS at both S=1 sites and I also have different orientations for the local D and g tensors.
When I use EasySpin least-square fitting the best parameters for the ZFS do not respect E<D/3. Is it a bug or something I did wrong ?
Here is my code
Code: Select all
% System spin [NiCuNi] S=3/2 ground state
clear
[B,spc]=textread('/Users/yves/ownCloud/Articles.en.cours/Marion.NiCuNi/simu.RPE/rpe.Me3pma4K.txt','%f,%f');
Sys.S = [1,1/2,1];
light=physconst('LightSpeed')
%J_cm=-110.
%JMHz = J_cm*100*light/1e6
%Sys.J = [JMHz 0 JMHz]
% valeurs dÈpart dernier fit
Sys.J=[-2937966.08840000,0,-2937966.08840000]
Sys.D=[4.5e+05 1.3e+05;0 0;6.8e+05 2.2e+05]
Sys.HStrain=[1.3765e+03 1.4439e+03 5.2889e+03]
Sys.g=[2.319 2.265 2.156; 2.071 2.117 2.419; 2.379 2.263 2.156] % valeurs sourav
Sys.DFrame=[2.0376 -0.7033 0.8251;0 0 0;1.7169 0.1327 -1.1239]
Sys.gFrame=[2.0666 -0.7086 2.3775;0 0 0; 0.1272 2.1334 -2.2044]
Exp.Range = [0 600];
Exp.Temperatue=[4.];
Exp.mwFreq = 9.337692204;
SimOpt.nKnots = 35;
%SimOpt.Method ='hybrid';
SimOpt.Method ='matrix';
Vary.D=[6e04 4e04;0 0;6e04 4e04]
%Vary.HStrain=[100. 100. 500.]
Vary.g=[0.03 0.03 0.03;0.03 0.03 0.03;0.03 0.03 0.03]
%Vary.DFrame=[2 2 2;0 0 0;2 2 2]*pi/180.
%Vary.gFrame=[2 2 2;0 0 0;2 2 2]*pi/180.
Sys0 = Sys;
Sys0.D = Sys.D;
%Sys0.HStrain=Sys.HStrain
Sys0.g=Sys.g
%Sys0.DFrame=Sys.DFrame;
%Sys0.HStrain=Sys.HStrain;
%FitOpt.Method = 'simplex';
FitOpt.Method = 'genetic';
FitOpt.PopulationSize=20;
%FitOpt.maxGenerations=30;
%FitOpt.Scaling = 'maxabs';
FitOpt.Scaling = 'lsq';
esfit('pepper',spc,Sys,Vary,Exp,SimOpt,FitOpt)
[H, I]= pepper(Sys, Exp, SimOpt);
plot(H, I*5000,'r',B,spc,'b');
data = [H(:) I(:)];
save('theo.RPE.Me3pma.glibre.genetic18.txt','data','-ascii');
hold on
%bestvalues: [481400 1.2868e+05 6.6052e+05 2.2622e+05 2.3119 2.2050 2.1560 2.0908 2.1580 2.4401 2.4330 2.2050 2.0960]