[Pw_forum] Questions about Thermal properties calculation

[xirainbow]

Dear john Bob:


> >Q1: Does pwscf have tools to calculate internal energe, specific heat,
> entropy?
>

I do not think QE give the tools to calculate specific heat.



> >Q2: I have a system with soft mode (negative phonon freq) in phonon
> dispersion. Is it >meaningful to calculate these thermal properties. If it
> still have physical meaning, how to >deal with the DOS below zero, abandon
> it or just add into the integration?
>
I think negative phonon freq is meanless if you deal with a equilibrium
state. You must elimilnate it. Maybe you can re-optimize the structure.


> >Q3: Using matdyn.x to get the full phonon dispersion, there are some
> discontiguous in >phonon bands. Is there a convenient way to get continual
> phonon dispersion?
>
I never meet this condition, therefore I do not fully know what you mean.
Can you upload the picture of phonon spectrum.


-- 
____________________________________
Hui Wang
School of physics, Nankai University, Tianjin, China
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