Author Topic: ionic dielectric constant  (Read 156 times)

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Offline baizq

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ionic dielectric constant
« on: July 20, 2021, 10:05 »
Dear All,

May I know how to calculate the ionic contribution to dielectric constant of materials? I have noticed that there is Optical spectrum functionality which returns dielectric tensor; but I guess this is just for the electronic contribution (correct me if I am wrong). Thanks !

Regards,
baizq
« Last Edit: July 20, 2021, 10:21 by baizq »

Offline Anders Blom

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Re: ionic dielectric constant
« Reply #1 on: July 21, 2021, 08:28 »

Offline baizq

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Re: ionic dielectric constant
« Reply #2 on: July 23, 2021, 11:16 »
Thank you Anders. I have a couple of quuestions regarding the SiO2 tutorial in the webpage you suggested.

1. In the optical spectrum session, huge number of bands are used (1000 bands above the fermi level and 1000 below). Why we need so many bands for such calculation?

2. In the DFT calculator setup, occupation_method is set as FermiDirac(100.0*Kelvin*boltzmann_constant). Why electron temperature is set to low value?