Dear Francesca, 400 iterations for reaching scf are very many.... there is something wrong in your setup... Are you sure that your coordinates are correct ? By visualizing your input with xcrysden I see that there are gaps in x and y directions (in addition to the probably desited one along z) ... hope it helps stefano
Francesca Costanzo wrote: > Dear PWSCF users, > > I am doing a scf calculation on si(100) slab surface. > I have tested two pseudo potentials fo silicon to see > which performs better. > > I am wondering why using > the Si.pbe-n-van.UPF and Si.pw91-n-van.UPF pseudoes > in the first case I can reach quite easily ( after 400 > iterations) the convergence while in the latter case after 1200 iterations > I still don't reach the convergence. > the mixing beta is 0.5. > > Is there something wrong? > > Anyway the input file is below: > > # self-consistent calculation > cat > si-ex01.in << EOF > &control > calculation='scf' > prefix='si', > tstress = .true. > tprnfor = .true. > restart_mode='restart', > pseudo_dir ='/sfs/sanfs/home/userincm/incbo407/PWscf/pseudo/', > outdir='/scratch/incbo407/au-PWscf/tmp-1/', > etot_conv_thr = 1.d-4 > / > &system > ibrav = 8, celldm(1) = 29.02243, celldm(2) =1.0, celldm(3)= 0.89771, > nat=56, ntyp=2, ecutwfc=18.0, > / > &electrons > mixing_mode = 'plain' > mixing_beta = 0.5 > conv_thr = 1.0d-8 > / > &ions > / > ATOMIC_SPECIES > Si 28.086 Si.pw91-n-van.UPF > H 1 H.pw91-van_ak.UPF > ATOMIC_POSITIONS {angstrom} > Si -.486986953827 -.486915661371 .021837699340 > Si 3.254734080912 3.254554580350 -.715466406181 > Si .424995921464 5.989287334956 -.032510900988 > Si 1.908574447668 7.596205581111 -.896329755432 > Si 5.990175519344 .425574367605 -.031655667742 > Si 7.597289525085 1.909448358802 -.895741285772 > Si 4.863694686691 4.863621862511 -.928089502092 > Si 9.019734606435 9.020000340300 -.836996926760 > Si 1.332006439043 4.282396930595 -1.483511378893 > Si 4.282762677873 1.331640602610 -1.482720710139 > Si 1.215421638705 9.726643706866 -1.436019240017 > Si 4.069065518611 6.940868463489 -1.558148325068 > Si 6.941730748367 4.070143770542 -1.556740812199 > Si 9.727400143869 1.215885487447 -1.436139812232 > Si 6.926671693616 9.825186228268 -1.480679150046 > Si 9.825040961721 6.927019069098 -1.481122837636 > Si 2.752199364097 -.023268345504 -2.733402882614 > Si -.022185141426 2.752036538539 -2.734578963613 > Si 2.755879272416 5.496899501655 -2.970326566691 > Si -.004779806850 8.317568614429 -2.969974442472 > Si 8.317316174588 -.004017804657 -2.969192076227 > Si 5.498360672151 2.755878723458 -2.968474960855 > Si 8.346177303503 5.558752009571 -2.782863187750 > Si 5.557877655641 8.346312021303 -2.782400281184 > Si 1.389966664098 1.388183764950 -4.139518840077 > Si 1.366337053897 6.940229376004 -4.258916306178 > Si 4.151574127028 4.149476803004 -4.278767316434 > Si 4.138929512730 9.694066210006 -4.160002340210 > Si 6.940071554385 1.366577579401 -4.258586275398 > Si 9.693861222560 4.139131304691 -4.160296524367 > Si 6.925553051516 6.926722417990 -4.154730726999 > Si 9.700291030289 9.701542440060 -4.273212145658 > Si .000000000000 .000000000000 -5.538591342479 > Si 2.769296729594 2.769296729594 -5.538591342479 > Si .000000000000 5.538591342479 -5.538591342479 > Si 2.769296729594 8.307892305490 -5.538591342479 > Si 5.538591342479 .000000000000 -5.538591342479 > Si 8.307892305490 2.769296729594 -5.538591342479 > Si 5.538591342479 5.538591342479 -5.538591342479 > Si 8.307892305490 8.307892305490 -5.538591342479 > H .847478422628 -.846884685755 -6.504440365581 > H -.847316494390 .847694326946 -6.503794769337 > H 3.610082118376 1.928241460414 -6.515886469477 > H 1.917014435899 3.621363118971 -6.495428477030 > H .852174341536 4.685717428620 -6.494724671289 > H -.840461532306 6.379649786722 -6.516156349874 > H 3.616235391428 7.460033933598 -6.504011732009 > H 1.921872283045 9.155369669764 -6.503953522512 > H 6.383803828126 -.844617690420 -6.508975414605 > H 4.685555500382 .852282293694 -6.494454790892 > H 9.156068183733 1.921926259125 -6.503307926268 > H 7.460679529841 3.616289367507 -6.504710245978 > H 6.385587155455 4.690845156163 -6.504170485184 > H 4.690683227924 6.386073998525 -6.503524888940 > H 9.160391561857 7.455445966849 -6.494835798512 > H 7.462679819843 9.153210626588 -6.508329818361 > K_POINTS {automatic} > 4 4 1 0 0 0 > EOF > > > thank you. > Francesca Costanzo >