Dear *?????? ?????? *
Have you tried the calculation considering spin polarization, nspin=2 and checking the convergence ? you can try a smaller degauss value using marzari-vanderbilt or gaussian too. Please check the smearing energy contribution to your total energy. Are the interface atoms in close distances from each other ? I mean 1.2-2.0 angstrom for instance. If not and you put them at far distances from each other you may relax a van der Waals interaction in which the pure DFT is weak. Do you really need such high amount of cutoff for energy and density ? I hope it helps. Best Wishes, m ---------------------------------------- Masoud Nahali SUT masoud.nahali at gmail.com alum.sharif.edu/~m_nahali On Mon, Apr 8, 2013 at 12:00 PM, *?????? ??????* wrote: > > Hi everybody, > > I am trying to optimize the structure of an interface between metal and > insulator but have difficulties with scf convergence. Here are the changes > in energies during scf cycle: > estimated scf accuracy < 17.58555120 Ry > estimated scf accuracy < 14.17435383 Ry > estimated scf accuracy < 2.05765892 Ry > estimated scf accuracy < 2.09375911 Ry > estimated scf accuracy < 1.37675281 Ry > estimated scf accuracy < 0.42594758 Ry > estimated scf accuracy < 0.29104539 Ry > estimated scf accuracy < 0.51143695 Ry > estimated scf accuracy < 0.18765814 Ry > estimated scf accuracy < 0.92590998 Ry > estimated scf accuracy < 0.93126088 Ry > estimated scf accuracy < 0.44023978 Ry > estimated scf accuracy < 0.33756785 Ry > estimated scf accuracy < 0.34216551 Ry > estimated scf accuracy < 0.36573444 Ry > estimated scf accuracy < 0.29089342 Ry > estimated scf accuracy < 0.29287805 Ry > estimated scf accuracy < 0.16940331 Ry > estimated scf accuracy < 0.17503222 Ry > estimated scf accuracy < 0.09708451 Ry > estimated scf accuracy < 0.07751341 Ry > estimated scf accuracy < 0.06774554 Ry > estimated scf accuracy < 0.15834930 Ry > estimated scf accuracy < 0.12269823 Ry > estimated scf accuracy < 0.12679734 Ry > estimated scf accuracy < 0.08558475 Ry > estimated scf accuracy < 0.04411767 Ry > estimated scf accuracy < 0.04754042 Ry > > I found similar posts on the forum ?but it didn't solve the problem. I > checked my structure with xcrysen...it seems to be ok. I am using USPP. > Any help and suggestions would be greatly appreciated. > > Thanks > > Here is my input: > &CONTROL > title = interface , > calculation = 'relax' , > restart_mode = 'from_scratch' , > wf_collect = .true. , > outdir = 'interface/' , > pseudo_dir = './' , > prefix = 'interface' , > lkpoint_dir = .true. , > disk_io = 'high' , > verbosity = 'high' , > nstep = 100 , > tstress = .false. , > tprnfor = .true. , > / > &SYSTEM > ibrav = 8, > celldm(1) = 9.3957, > celldm(2) = 1.7321, > celldm(3) = 6.0000, > nat = 72, > ntyp = 3, > ecutwfc = 50 , > ecutrho = 500 , > nbnd = 500, > occupations = 'smearing' , > degauss = 0.025 , > smearing = 'methfessel-paxton' , > nspin = 1 , > / > &ELECTRONS > electron_maxstep = 200, > conv_thr = 1.0d-6 , > mixing_mode = 'local-TF' , > mixing_beta = 0.1 , > mixing_ndim = 8 , > / > &IONS > ion_dynamics = 'bfgs' , > / > ATOMIC_SPECIES > ? BR, > > N V > -------------------------------------------------------------------------------------------------------------------- -------------- next part -------------- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20130408/a5191cad/attachment.html
