[Q-e-developers] system size

[Paolo Giannozzi]

On Thu, 2013-04-25 at 15:14 -0500, Laalitha Liyanage wrote:

> 792 atom system is  too large for Quantum Espresso.

not true. It depends upon which kind of calculations one want
to run, upon the needed cutoff and k-points, upon the machine 
you have access to. If Gamma-point sampling and a moderate cutoff 
(25 to 35 Ry) are sufficient, simple structural optimization or
Car-Parrinello molecular dynamics can be performed on a few 
hundreds processors of a serious parallel machine. It requires
some serious understanding of how the code, and in particular
the parallelization, works, though.

P.

-- 
Paolo Giannozzi, Dept. Chemistry&Physics&Environment, 
Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222