> > what "Temperature dependent DFT" would encompass. > > In my mind, all the first principles/ab initio calculations only work > under 0K, so I want to know whether can I do the first principles/ab > initio calculations under other temperatures other than 0K, especially > under some temperatures around room temperature?
first of all, the way people talk about ab initio being calculations at OK usually has to be seen in the context of geometry optimizations. this approach generally uses the time independent DFT formalism and thus the Born-Oppenheimer approximation and with in that approximation you can very well do molecular dynamics, i.e. a system at temperature different from OK. you can do this with pw.x but also in cp.x using the car-parrinello hamiltonian. of course there is the effect of temperature to the electronic structure, but that is is generally very small, unless you go to very high temperatures. this can be treated as well, but require some more complicated to use methods. in most cases, you should be just fine by applying a finite temperature to your atoms and using normal DFT. cheers, axel. > > Kind regards, -- ======================================================================= Axel Kohlmeyer akohlmey at cmm.chem.upenn.edu http://www.cmm.upenn.edu Center for Molecular Modeling -- University of Pennsylvania Department of Chemistry, 231 S.34th Street, Philadelphia, PA 19104-6323 tel: 1-215-898-1582, fax: 1-215-573-6233, office-tel: 1-215-898-5425 ======================================================================= If you make something idiot-proof, the universe creates a better idiot.
