Mr. Phonon ?
Yap, recently I got some interst in his preopoerties...some time acoustic and some time optical...
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I used Dario Alfe's code PHON to calculate the phonon, which is based on 'small displacement' method ( a numerical way Vs. linear response method).
Here I will present my calc. of ZPE of some systems with PHON code and with linear response methods: say, with QuantumEspress.
