[Pw_forum] phonon & temperature

[Mehrnaz Anvari]

Dear Paolo
First of all thanks a lot because of your answer. But, I have to make my 
question clear.As you said for phonon calculations, external potential 
depends on ionic displacements, and these diplacements are enough small to 
provide harmonic conditions (I agree with this part). So, phonons can be 
calculated and it means tempreture isn't used directly. In. addition the  
source of these displacements in crystals is temperature, and it sometimes 
causes that crystal doesn't  have     smooth  surface for example in room 
temperature. now, I want to know that can I say that the calculations 
consist of this surface flactuations?
Best
Mehrnaz     
 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20091115/259c0155/attachment.html>