Didn't even realize what I had typed. That is what happens when you are running from one place to the next :^)
Thanks to Paolo for explaining things more eloquently. On 2/15/07, Paolo Giannozzi <giannozz at nest.sns.it> wrote: > > > On Feb 15, 2007, at 16:37 , Nichols A. Romero wrote: > > > There are two ways to solve for the KS ground state. > > 1. Direct minimization of KS functional > > 2. Self-consistently solving the KS eqn. > > > > The conjugate-gradient (cg) in PWSCF and CP are not doing > > different things same thing. > > let me say something different the same thing :-) > > 'cg' in PWscf: *self-consistency + fixed-potential diagonalization* > The diagonalization is performed by transforming the secular > problem into a minimum problem (nothing really fancy: > min <\psi|H\psi> + orthogonality) and solving for each band > in sequence, using conjugate gradient. Slower than Davidson > diagonalization, uses less memory. To be used in case of trouble > with Davidson or if memory is tight. > > 'cg' in CP: conjugate-gradient algorithm for minimization of the > *energy functional* (global minimization). > > Paolo > --- > Paolo Giannozzi, Democritos and University of Udine, Italy > > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum > -- Nichols A. Romero, Ph.D. 1613 Denise Dr. Apt. D Forest Hill, MD 21050 443-567-8328 (C) 410-306-0709 (O) -------------- next part -------------- An HTML attachment was scrubbed... URL: /pipermail/attachments/20070215/22e0107b/attachment.htm
