Dear Dipak Thakur, I don't know about the system and have not fully understood your problem, nor seen any figure, but I would recommend you to double check the input coordinates: you are plenty of O atoms very close to each other, see for example atom number 84 and 85 (76pm!).
And, the input file you sent us does not correspond to a slab. You might want to use "K_POINTS Gamma". HTH Guido Il 12/23/2011 02:53 PM, Dipak Thakur ha scritto: > Dear All, > > I am trying to optimize hydroxyapatite 1x1x2 and 1x1x1. > However, the atoms in the unit cell move into vacuum above the slab. See > the figure below. > > That is while optimization [scf] all the atoms move such that they > occupy the vacuum above. > I have worked with graphene but never faced such problems. > > Can any one help me understanding why this might be happening. > Below is my input file. > > ---------------------------------------------------------------------------------------------------------------------------------------------- > &CONTROL > Calculation = "relax" , > restart_mode = 'from_scratch' , > outdir ='/usr/espresso-4.3.2/', > pseudo_dir = '/usr/espresso-4.3.2/pseudo/', > disk_io = 'default' , > verbosity = 'default' , > etot_conv_thr = 1.D-4 , > forc_conv_thr = 1.D-3 , > nstep = 500 , > dt = 40 , > / > &SYSTEM > ibrav = 0, > nat = 96, > ntyp = 4, > ecutwfc = 10 , > ecutrho = 80 , > occupations = 'smearing' , > degauss = 0.02 , > / > &ELECTRONS > electron_maxstep = 300, > Conv_thr = 1.0d-8 , > mixing_mode = 'plain' , > mixing_beta = 0.5 , > diagonalization = 'cg' , > diago_cg_maxiter = 50, > / > &IONS > / > CELL_PARAMETERS > 17.80868385387 0.00000000000 0.00000000000 > -8.90434192693 15.42277262532 0.00000000000 > 0.00000000000 0.00000000000 25.99871311373 > ATOMIC_SPECIES > Ca 40.07800 Ca.pz-n-vbc.UPF > P 39.09830 P.pz-van_ak.UPF > O 15.99940 O.pz-van_ak.UPF > H 1.007940 H.pz-van_ak.UPF > ATOMIC_POSITIONS angstrom > Ca -0.4710847875E-11 5.440920259 0.1031844561E-01 > Ca -0.4710847875E-11 5.440920259 6.889282188 > Ca 4.711975164 2.720460129 13.74760904 > Ca 4.711975164 2.720460129 6.868645296 > Ca 4.711975164 2.720460129 3.449800317 > Ca 4.711975164 2.720460129 10.32876406 > Ca 0.4713197894E-11 5.440920259 3.429163425 > Ca 0.4713197894E-11 5.440920259 10.30812717 > Ca -2.355045187 8.107515277 1.719740935 > Ca -2.355045187 8.107515277 8.598704677 > Ca 7.067020351 0.5386511056E-01 12.03818655 > Ca 7.067020351 0.5386511056E-01 5.159222806 > Ca 1.225113543 2.014228680 5.159222806 > Ca 1.225113543 2.014228680 12.03818655 > Ca 3.486861621 6.147151708 1.719740935 > Ca 3.486861621 6.147151708 8.598704677 > Ca -1.131816434 2.068093790 1.719740935 > Ca -1.131816434 2.068093790 8.598704677 > Ca 5.843791598 6.093286598 12.03818655 > Ca 5.843791598 6.093286598 5.159222806 > P 2.020966148 3.007468673 1.719740935 > P 2.020966148 3.007468673 8.598704677 > P 2.691009016 5.153911715 12.03818655 > P 2.691009016 5.153911715 5.159222806 > P -1.594061198 3.253942361 5.159222806 > P -1.594061198 3.253942361 12.03818655 > P 6.306036362 4.907438027 1.719740935 > P 6.306036362 4.907438027 8.598704677 > P 5.808922982 0.2464736877 1.719740935 > P 5.808922982 0.2464736877 8.598704677 > P -1.096947818 7.914906700 12.03818655 > P -1.096947818 7.914906700 5.159222806 > O 0.8104597282 3.956637212 1.719740935 > O 0.8104597282 3.956637212 8.598704677 > O 3.901515436 4.204743176 12.03818655 > O 3.901515436 4.204743176 5.159222806 > O 6.402631853 2.680197319 5.159222806 > O 6.402631853 2.680197319 12.03818655 > O -1.690656689 5.481183068 1.719740935 > O -1.690656689 5.481183068 8.598704677 > O 0.8801969606 6.884940495 1.719740935 > O 0.8801969606 6.884940495 8.598704677 > O 3.831778203 1.276439893 12.03818655 > O 3.831778203 1.276439893 5.159222806 > O 3.343146379 3.795858018 1.719740935 > O 3.343146379 3.795858018 8.598704677 > O 1.368828785 4.365522369 12.03818655 > O 1.368828785 4.365522369 5.159222806 > O -1.615736284 4.793178702 5.159222806 > O -1.615736284 4.793178702 12.03818655 > O 6.327711448 3.368201686 1.719740935 > O 6.327711448 3.368201686 8.598704677 > O 4.465067665 0.9973206834 1.719740935 > O 4.465067665 0.9973206834 8.598704677 > O 0.2469074986 7.164059704 12.03818655 > O 0.2469074986 7.164059704 5.159222806 > O 2.023793333 2.104820002 0.4829032547 > O 2.023793333 2.104820002 7.361866997 > O 2.688181831 6.056560386 13.27502423 > O 2.688181831 6.056560386 6.396060487 > O -0.8109309257 2.805066439 3.922385126 > O -0.8109309257 2.805066439 10.80134887 > O 5.522906090 5.356313949 2.956578616 > O 5.522906090 5.356313949 9.835542358 > O 6.589226069 0.7002464373 0.4829032547 > O 6.589226069 0.7002464373 7.361866997 > O -1.877250905 7.461133951 13.27502423 > O -1.877250905 7.461133951 6.396060487 > O 2.688181831 6.056560386 3.922385126 > O 2.688181831 6.056560386 10.80134887 > O 2.023793333 2.104820002 2.956578616 > O 2.023793333 2.104820002 9.835542358 > O 5.522906090 5.356313949 0.4829032547 > O 5.522906090 5.356313949 7.361866997 > O -0.8109309257 2.805066439 13.27502423 > O -0.8109309257 2.805066439 6.396060487 > O -1.877250905 7.461133951 3.922385126 > O -1.877250905 7.461133951 10.80134887 > O 6.589226069 0.7002464373 2.956578616 > O 6.589226069 0.7002464373 9.835542358 > O 0.000000000 0.000000000 1.341397930 > O 0.000000000 0.000000000 8.220361672 > O 0.000000000 0.000000000 12.41652955 > O 0.000000000 0.000000000 5.537565812 > O 0.000000000 0.000000000 4.780879801 > O 0.000000000 0.000000000 11.65984354 > O 0.000000000 0.000000000 2.098083941 > O 0.000000000 0.000000000 8.977047683 > H 0.000000000 0.000000000 0.4182409955 > H 0.000000000 0.000000000 7.297204737 > H 0.000000000 0.000000000 13.33968649 > H 0.000000000 0.000000000 6.460722746 > H 0.000000000 0.000000000 3.857722866 > H 0.000000000 0.000000000 10.73668661 > H 0.000000000 0.000000000 3.021240875 > H 0.000000000 0.000000000 9.900204617 > K_POINTS automatic > 1 1 1 0 0 0 > ---------------------------------------------------------------------------------------------------------------------------------------------- > > > > > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum -- Guido Fratesi Dipartimento di Scienza dei Materiali Universita` degli Studi di Milano-Bicocca via Cozzi 53, 20125 Milano, Italy
