Addition of an unpaired electron when modelling a polymer
Posted: Mon Jun 06, 2016 1:17 am
Hi all,
I am relatively new to EasySpin and am a bit confused in the justification of adding in an additional electron to match my experimental spectra to my simulated spectra. The experimental spectra I have comes from defects in polymers and I see, in general, a EPR spectrum with a "shoulder". I am irradiating these polymers with charged particles to different doses. As the polymer becomes more damaged, this shoulder increases in size and also broadens.
I have attempted a simulation using a DFT GIPAW method for a spin 1/2 system. This code outputs a single g-tensor for different damaged systems which I am plotting using the pepper regime (as I think this is the most appropriate). When I refer to damage in the computational model, I simply remove C-H bonds from the system. The problem I am having is that the single electron g-tensor for the damage system does not give me the shape I see experimentally. However, adding in an additional electron (with a g-tensor similar to the free electron's one) does. My only explanation is that, as the system becomes more damaged, additional electrons are detected in the system from my experimental results.
Am I justified, however, in adding in this addition electron and its g-tensor? Or would it be "safer" to just add in the damaged electrons g-tensor? Please let me know what you think. If you require additional information I would be happy to supply it.
Here is a sample of code I am using. I have set the A-tensor and spin-spin tensor components to 0 for simplicity.
Thank you for your time!
I am relatively new to EasySpin and am a bit confused in the justification of adding in an additional electron to match my experimental spectra to my simulated spectra. The experimental spectra I have comes from defects in polymers and I see, in general, a EPR spectrum with a "shoulder". I am irradiating these polymers with charged particles to different doses. As the polymer becomes more damaged, this shoulder increases in size and also broadens.
I have attempted a simulation using a DFT GIPAW method for a spin 1/2 system. This code outputs a single g-tensor for different damaged systems which I am plotting using the pepper regime (as I think this is the most appropriate). When I refer to damage in the computational model, I simply remove C-H bonds from the system. The problem I am having is that the single electron g-tensor for the damage system does not give me the shape I see experimentally. However, adding in an additional electron (with a g-tensor similar to the free electron's one) does. My only explanation is that, as the system becomes more damaged, additional electrons are detected in the system from my experimental results.
Am I justified, however, in adding in this addition electron and its g-tensor? Or would it be "safer" to just add in the damaged electrons g-tensor? Please let me know what you think. If you require additional information I would be happy to supply it.
Here is a sample of code I am using. I have set the A-tensor and spin-spin tensor components to 0 for simplicity.
Code: Select all
Sys.S = [1/2, 1/2];
Sys.g = [2.00114645936182 2.00210284596182 2.00330932796182; 2.00231935436182 2.00231932436182 2.00231935436182];
Sys.Nucs = '1H, 12C';
Sys.A = [0 0 0 0 0 0; 0 0 0 0 0 0];
Sys.lw = [0.05 0.01]
Sys.tcorr = 1e-7;
Sys.ee = [0 0 0];