There is an extensive documentation at the EasySpin website including examples! As introduction to MATLAB and EasySpin this may help: http://easyspin.org/pubs/easyspin_slides.pdf 

Thank you very much, Dr. René Schnorr. It would helpful to me.

Dear Duraiyarasu, 

you need to install the last version of EasySpin in Matlab. Frequently is available a new version of EasySpin and you need to install the new version when it been available. After that, you need a input containing the .dat of your data, types of paramagnetic centers, width and bordering of lines and at the end of input file (Matlab) lines containing the transformation of the experimental and simulated spectra in the file .dat. You must change the parameters of the input (Matlab) until reach the best simulated spectra.

Dear Dr.Felipe de Souza Vilhena, 

Thank you very much for your answer. As you said, I have installed Matlab and latest version of Easy spin also. The thing is that I could not able to work in Matlab since it is a command based program which I don't have experience. 

Follows an input for Matlab to simulate an EPR spectrum with EasySpin.

You need save your experimental spectrum to file .dat in C:.

Change the name in the second line 'Cu_solido_1.dat'

Put the experimental frequency in 'Exp.mwFreq = 9.743106';

Put the range of experimental spectrum in ' Exp.Range = [288.60 366.45];'

Pepper function is for solid state and N2 temperature. Garlic function is for aqueous solution in room temperature.

Press the button to run simulation, and change values in the lines: Sys.g = [2.06 2.2]; Sys.lwpp =[1 0.5]; %Sys.HStrain = [360 00 600]; to reach the best simulation.

Hi, Modhi Edhbaiah

You need to install Easyspin at Matlab!!

What is your system?