Questions tagged [quasi-harmonic-approximation]
For questions regarding the quasi-harmonic-approximation.
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Is there an upper limit of temperature after which the quasi-harmonic approximation (QHA) fails?
I can't seem to articulate what made me ask this question but it sprang up when I asked: What does it mean to say a material is 'anharmonic'?.
I've heard before that the electronic entropy ...
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What does it mean to say a material is 'anharmonic'?
I understand that a harmonic picture of the potential in a material isn't enough to study lattice dynamics thoroughly. The quasi-harmonic approximation is a good workaround and helps incorporate ...
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Phonon density of states as a function of frequency vs energy [closed]
Lattice dynamics codes like Phonopy output density of states, $g_{(\omega)}$, as a function of frequency. Since $\int g_{(\omega)}d\omega$ is the number of states ...
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What do phonon dispersion (or lattice dynamics) studies include?
I use the codes phonopy and phonopy-qha for phonon dispersion studies. phonopy-qha gives ...