[QE-users] Calculation of dielectric function for high electonic temperature

[Roman Voronkov]

Hello dear colleagues

I'm trying to perform calculations of dielectric function of  Al2O3 using
epsilon.x at the condition of high electronic temperature (0-4 eV).

For zero temperature I got reasonably good result - it coincides well with
experiments. But when I increase "degauss" up to 1-3 eV I get strange
results like negative eels spectrum around band gap energy or disobeing the
f-sum rule.

So the question is do such calculations in principle meaningfull in QE? And
- if yes - should I use any specific parameters for such calculations? The
formula in epsilon.x manual should work I guess for any kind of occupation
numbers distribution. But maybe I'm missing something?

Input file for 2eV is attached.

Best regards,
Roman Voronkov
LPI RAS
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