On Sat, 5 Jul 2008, zhaohscas wrote: HZ> Hi all,
hi! HZ> When the system under study is large, i.e., including hundreds of HZ> atoms or more, in this case, form the point of balancing the HZ> efficiency and veracity, whether the PWscf is suitable for such HZ> computation or not? Furthermore, in this case, which will be more HZ> promising DFT code(s)? this is a strange kind of question to ask to a mailing list that supports a specific code. what do you expect people to answer? QE is complete crap and does not run correctly on anything and does not scale to boot?? you are better off using code X??? i hope not. of course, QE does run as accurate as possible within the confines of using DFT with plane waves and pseudopotentials, modulo the occasional bug that every large, versatile and thus complex software package contains. of course we would like you to use it and not something else. of course, that are weaknesses, but the code offers a lot of possiblilities for good performance and scaling and people are continuously trying to improve it. it cannot beat the scaling of the underlying physics, though, and one always has to make a tradeoff between the flexibility, capabilities, and maintainability of a code and its absolute performance. since there is no "one-size fits all" kind of solution, the best choice of approach (and thus code) always depends on the specific problem at hand. HZ> Any help or hints would be appreciated. my suggestion: try it and see for yourself. cheers, axel. HZ> Sincerely yours, HZ> -------------- HZ> Hongsheng Zhao <zhaohscas at yahoo.com.cn> HZ> Xinjiang Technical Institute of Physics and Chemistry HZ> Chinese Academy of Sciences HZ> GnuPG DSA: 0xD10849 HZ> 2008-07-05 HZ> HZ> _______________________________________________ HZ> Pw_forum mailing list HZ> Pw_forum at pwscf.org HZ> http://www.democritos.it/mailman/listinfo/pw_forum HZ> -- ======================================================================= 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.
