Quite hard to say with the naked eye... A few suggestions:
1) get a structure file (cif) file from a repository (crystallography.info etc) and convert it to an QE input file using the script cif2cell with the option -p quantum-espresso 2) check structure files published by other groups (I think https://github.com/WMD-group/hybrid-perovskites had plenty of); it is easy to convert the crystal structure to QE format ... Finally, check how it looks by xcrysden (xcrysden --pwi input_file_name); set the correct unit cell repetition to avoid overlapping periodic cells; PS: for MAPbI3 (and all related) spin-orbit coupling plays a large role in the band-structure HTH Chris Message: 10 Date: Wed, 1 Mar 2017 14:35:37 +0530 From: Saurabh Kumar <saurabhkumar651...@gmail.com> Subject: [Pw_forum] Atomic positions of atoms in hybrid perovskite CH3NH3PbI3 ? To: pw_forum@pwscf.org Message-ID: <CAFiy4VhsQaL6erZ=bV3zoe=rkskzsucujt9efpt1skw8clw...@mail.gmail.com> Content-Type: text/plain; charset="utf-8" Dear All, I am trying to calculate band structure of hybrid perovskite CH3NH3PbI3. please suggest me the atomic position of atoms in hybrid perovskite CH3NH3PbI3. I make a file for hybrid perovskite CH3NH3PbI3. &CONTROL calculation = 'scf' , outdir = 'CH3NH3PbCl3' , pseudo_dir = '.' , prefix = 'calc' , verbosity = 'low' , tstress = .false. , tprnfor = .false. , / &SYSTEM ibrav = 6, celldm(1) = 16.772175819192d0, celldm(3) = 1.427919554d0, nat = 48, ntyp = 5, ecutwfc = 30 , ecutrho = 300 , input_dft = 'lda' , / &ELECTRONS conv_thr = 1d-06 , mixing_mode = 'plain' , mixing_beta = 0.700d0 , diagonalization = 'david' , / ATOMIC_SPECIES Cl 35.45300 Cl.pz-n-rrkjus_psl.0.1.UPF Pb 207.20000 Pb.pz-dn-rrkjus_psl.0.2.2.UPF C 12.01000 C.pz-n-rrkjus_psl.0.1.UPF N 14.00670 N.pz-n-rrkjus_psl.0.1.UPF H 1.00794 H.pz-rrkjus_psl.0.1.UPF ATOMIC_POSITIONS {crystal} Pb 0.937020143 -1.381620552 2.098848798 Cl 3.211929739 0.317599239 1.844273817 Cl 2.699872755 1.301845443 -3.305788426 Pb 0.964431461 -1.008900183 -3.532207636 Cl -0.489754419 -3.511397613 -3.633088932 Cl 1.034885395 -1.534215680 -0.759835038 Cl 1.409893953 -1.285797523 4.938867114 Cl -1.132155996 0.537298685 2.399452065 Pb -3.080944681 2.580388321 2.231991058 Cl -3.279652103 3.073405815 5.085611211 Cl 2.703232904 -3.640473759 2.225540867 Cl 3.347432086 -2.614462807 -3.350845770 Cl -1.134693736 -3.338622116 2.539171237 Cl -1.378510211 0.684905164 -3.215713026 Pb -2.973784309 3.022014726 -3.468219920 Cl -3.189002236 2.822985615 -0.579682726 C 1.011249439 2.100007146 4.846637634 N 0.768103727 3.569701583 4.900244063 H 1.391401901 1.843649875 3.850768134 H 1.746556583 1.834665268 5.616021108 H 0.062189194 1.581313485 5.022904990 H 0.406354704 3.873014073 5.836799757 H 1.632027238 4.102254012 4.702229080 H 0.072765972 3.875031075 4.176030363 C 5.346104178 -0.892597492 5.376031513 N 4.556882827 -1.662165641 4.369176663 H 5.057137431 -1.239196765 6.374216016 H 6.413413086 -1.069268376 5.196888416 H 5.117813950 0.175515396 5.266776856 H 4.771458453 -1.350482932 3.407072251 H 4.746496105 -2.685664408 4.434941757 H 3.528634541 -1.528108529 4.524757283 C 0.602056880 2.494670338 -0.198488995 N 1.599120434 3.253212641 -1.010040233 N 4.494548212 -0.640988937 -1.050826182 C 5.452038014 -1.591220629 -0.416658882 H 1.019923491 1.507847799 0.035942296 H 0.405831256 3.047246714 0.727770443 H -0.320919033 2.386376409 -0.780236952 H 1.299347740 4.237973746 -1.174416380 H 2.528500760 3.284664511 -0.540992123 H 1.765769882 2.779408882 -1.926239918 H 4.889643075 -2.438266266 -0.008625119 H 6.159405961 -1.941750558 -1.177483464 H 5.987760207 -1.066352016 0.382960466 H 5.004402403 0.128660156 -1.526288120 H 3.934931011 -1.136283995 -1.781604973 H 3.860276085 -0.233082640 -0.332648827 K_POINTS {automatic} 8 8 8 0 0 0 is this correct or not? Best wishes . _______________________________________________ Pw_forum mailing list Pw_forum@pwscf.org http://pwscf.org/mailman/listinfo/pw_forum