[Wien] regarding dielectric constant

[Dr. K. C. Bhamu]

Dear Prof. Peter

This is in continuation with my previous query for excitation binding
energy and dielectric constant.
The first line of the case.epsilon is:

# Energy [eV] Re_eps_xx     Im_eps_xx     Re_eps_zz     Im_eps_zz
#
   0.013610  0.556574E+01  0.571125E-01  0.557539E+01  0.591910E-01

According to this data, the static dielectric constant comes out to be:
~5.56. What does it mean? Should it be considered for low frequency
dielectric constant?
In our measured value we are getting low frequency dielectric constant ~18
which is quite larger than calculated. We tried to calculate low frequency
dielectric constant using plazma frequency and we got it 17.8 which is
nearly equal to the measured value. For this we used average band-gap value


In the literature I am getting low frequency dielectric constant value
between epslion_0 17-24 and at epscilon_infinite ~4-6 for CH3NH3PbI3.

I need any comments on it.

Now using the average band-gap, we calculated " excitation binding energy"
which is now ~8 far below the experimental value 13.
This difference in the excitation binding energy may be due to no-inclusion
of the SO effect (or mBJ+SO as per your suggestion in last email).


Kind regards
Bhamu
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