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eminamitani / thermal_conductivity_code

Allen-Feldman thermal conductivity compatible to GULP implementation
MIT License
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Bug fix for non cubic cell #4

Closed eminamitani closed 3 years ago

eminamitani commented 3 years ago

In some test, the result of thermal conductivity is overestimated. This may due to some bug in the nearest distance. Thus, try calculation in non-cubic cell and check the value of the nearest distance.

eminamitani commented 3 years ago

I have tested anisotropic cell for SiO2 but it seems OK. The origin of the problem is not sure...

eminamitani commented 3 years ago

Strange large diffusivity is not from cell. That is caused by 1/omega contribution for artificial small frequency mode. As tentative fix, I set the threshold in get_Sij as

   inv_omega=np.zeros(nmodes)
    for i in range(nmodes):
        #tentative
        if omega[i] >0.1:
            inv_omega[i]=1.0/np.sqrt(omega[i])
        else:
            inv_omega[i]=0.0

This is not so good way. The better solution is acoustic sum rule to avoid negative frequency