Your ecutwfc is too low. Check that. and ecutrho should be 8-10 times ecutwfc. The celldm(1) cannot be 1.0. What are the units? check that.
On Fri, Aug 27, 2010 at 11:29 AM, joaquin peralta <jperaltac at gmail.com>wrote: > Dear pw_forum > > I try to simulate a metallic slab under a electric field. In order to > improve the convergence, I checked this web page : > > http://blog.sina.com.cn/s/blog_5f15ead20100cw4d.html > > I tried all the suggestion (except band number increase) and the process > continue with a very slow convergence, after 283 iterations the ethr=1.2E-9. > The important part of the input file is : > > &CONTROL > calculation = 'scf' > ... > tefield = .true. > dipfield = .true. > / > &SYSTEM > ibrav = 0 > celldm(1) = 1.0 > nat = 21 > ntyp = 1 > ecutwfc = 30 > ecutrho = 500 > degauss = 0.03 > occupations = 'smearing' > smearing = 'mv' > nspin = 2 > starting_magnetization= 0.1 > edir = 3 > emaxpos = 0.9 > eopreg = 0.2 > eamp = 0.019447 > / > &ELECTRONS > electron_maxstep = 300 > mixing_mode = 'local-TF' > mixing_beta = 0.1 > mixing_ndim = 10 > / > ... > K_POINTS (automatic) > 6 6 6 0 0 0 > ... > This process use approx 5Gb of data in the associated files. > > My question are, > -If I increase the band number, The space disk will be more? > -Do you have suggestion about how to proceed in order to avoid this I/O > increase. and improve the convergence or velocity. > -I'm (over/under)estimating some previous value?, k-points, mixing_*, > ecut*? > > Thanks in advance > Joaquin Peralta > Materials Science and Engineering > Iowa State University. > > -- > ---------------------------------------------------- > Group of NanoMaterials > ---------------------------------------------------- > http://www.gnm.cl > ---------------------------------------------------- > Joaqu?n Andr?s Peralta Camposano > ---------------------------------------------------- > http://www.lpmd.cl/jperalta > > In a world without frontiers, > who needs Gates and Win. > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum > > -- Karthik Guda Graduate Student Materials Engineering Purdue University -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20100827/bb265a3c/attachment-0001.htm
