On Fri, 2 Nov 2007, M.Sairam Swaroop wrote: | Dear Siesta Users, | | I would be grateful if somebody could point out to me when to use the | molecular dynamics as implemented in siesta. | | As a first assumption from the papers which have reported results using | ab-initio MD with siesta, i get the impression that this would be useful | for for systems where the CG convergence of forces is not readily | achievable (eg, systems like ionic liquids). Or is this done to getting | information of the system which generally cannot be got form relaxation | runs. | | I would be nice if someone could comment on this issue.
Dear Sairam: an answer to "when to use the molecular dynamics" could be "when you are interested in DYNAMIC properties" (time correlation functions etc.) MD is not a substitute to CG and serves in fact a quite different purpose: in CG you search the energy minimum, whereas in the MD the energy is either constant, or fluctuating around a mean value (with a thermostat). However, in principle one can use simulated anealing as a dynamical procedure to achieve the (~global) minimum, but this is tricky. Check the tutorials by Marivi Fernandez-Serra on molecular dynamics, SIESTA page -> Tutorials -> Lyon, 18-22 June 2007 -> 21 June Best regards Andrei +-- Dr. Andrei Postnikov ---- Tel. +33-387315873 ----- mobile +33-666784053 ---+ | Paul Verlaine University - Institute de Physique Electronique et Chimie, | | Laboratoire de Physique des Milieux Denses, 1 Bd Arago, F-57078 Metz, France | +-- [EMAIL PROTECTED] ------ http://www.home.uni-osnabrueck.de/apostnik/ --+ If possible, please avoid sending me Word or PowerPoint attachments. http://www.gnu.org/philosophy/no-word-attachments.html
