Re: [SIESTA-L] speed up the MD nose calculation
Dear Bipul, i am using the nose MD calculation for liquid tin, with 120 atoms But the calculations are going really slow. Since siesta can made mainly for MD calculations, so the calculations must be fast. SIESTA able to do only 300 or 400 step in a whole day with 8 processors. If you refer to ionic steps (I mean, if you get a MD step = 400) I would say this is not that bad if you stick to the DFT level. I can't say that it's fast, but it's not slow either. Riccardo -- Riccardo Rurali Escola Tècnica Superior d'Enginyeria (ETSE) Universitat Autònoma de Barcelona (UAB) Campus de la UAB 08193 Bellaterra (Barcelona) Spain tel.: +34 93 581 3531 fax.: +34 93 581 2600 e-mail: [EMAIL PROTECTED]
[SIESTA-L] speed up the MD nose calculation
hello siesta user, i am using the nose MD calculation for liquid tin, with 120 atoms But the calculations are going really slow. Since siesta can made mainly for MD calculations, so the calculations must be fast. SIESTA able to do only 300 or 400 step in a whole day with 8 processors. and i think it is really slow. Here i am using 100 Ry mesh cutoff which is too lowi have to use about 300 Ry. But then the calculations are more slower than that.. Can anybody just look in the input file and suggest me what to modify to speed up the calculations i attached the sn.fdf file with that mail. - Why delete messages? Unlimited storage is just a click away. sn.fdf Description: 151130065-sn.fdf
Re: [SIESTA-L] question about energy of a single atoms
On Tue, 4 Sep 2007, bipul rakshit wrote: | hello siesta user, | i am doing calculations on Sn (tin)... | i do the convergence test for mesh cutoff and monhorsk pack. | the cubic Sn converges at 8x8x8 and mesh cutoff of 268 Ry. Since i use 8 atoms per unit cell so i get 512 atoms (auxillary supercell 4x4x4) | | Now my question is | 1. when i run siesta with the above parameters and at the end of the file the energy it give is the energy of 512 atoms or what Dear Bipul, the total energy is given per the number of atoms you really have in your cell, i.e. 8 in your case. The auxillary supercell is an artificial construction to facilitate keeping trace on overlaps across the cell boundary, in systems with periodicity. | 2. If its the energy of 512 atoms then how to find the energy of single atom, in the same volume occupied by a single atom?? To get total energy per atom, you divide your result by 8. I don't quite understand "in the same volume occupied by a single atom". All all 8 atoms structurally equivalent? 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/ --+
[SIESTA-L] question about energy of single atom
hello siesta user, i am doing calculations on Sn (tin)... i do the convergence test for mesh cutoff and monhorsk pack. the cubic Sn converges at 8x8x8 and mesh cutoff of 268 Ry. Since i use 8 atoms per unit cell so i get 512 atoms (auxillary supercell 4x4x4) Now my question is 1. when i run siesta with the above parameters and at the end of the file the energy it give is the energy of 512 atoms or what 2. If its the energy of 512 atoms then how to find the energy of single atom, in the same volume occupied by a single atom?? mean just want to ask how to get the energy per atom - Try the revolutionary next-gen Yahoo! Mail. Click here.
[SIESTA-L] question about energy of a single atoms
hello siesta user, i am doing calculations on Sn (tin)... i do the convergence test for mesh cutoff and monhorsk pack. the cubic Sn converges at 8x8x8 and mesh cutoff of 268 Ry. Since i use 8 atoms per unit cell so i get 512 atoms (auxillary supercell 4x4x4) Now my question is 1. when i run siesta with the above parameters and at the end of the file the energy it give is the energy of 512 atoms or what 2. If its the energy of 512 atoms then how to find the energy of single atom, in the same volume occupied by a single atom?? - Unlimited freedom, unlimited storage. Get it now
