<div dir="ltr">Dear PW users,<div>I'm trying to do a band structure calculation for bi2se3, but the resulting band structure does not look like other DFT calculations as it is missing the 0.3eV band gap. I also tried uploading my input file to SeeK-Path and the crystal structure looked wrong and deformed. Below are my vc-relax and band input files, is there something I'm missing? I'm using v6.5 on a CentOS 8 Vmware workstation (Sorry, new to DFT calculations).</div><div><br></div><div>&control<br> calculation = 'vc-relax'<br> prefix='bi2se3rel'<br> restart_mode = 'from_scratch'<br> outdir= '/home/name/QEoutput'<br> pseudo_dir='/home/name/quantum_espresso/q-e-qe-6.5/pseudo'<br> etot_conv_thr = 1e-7<br> forc_conv_thr = 1e-6<br>/<br>&system<br> ibrav = -5, celldm(1) = 18.6947, celldm(4) = 0.9135, nat = 5, ntyp = 3,<br> ecutwfc = 40, ecutrho = 500,<br> rhombohedral = .true.,<br> noncolin=.true.,lspinorb=.true.,starting_magnetization=0.,<br> nbnd=78,<br> vdw_corr = 'grimme-d2'<br>/<br>&electrons<br> conv_thr = 1.0e-9,<br>/<br>&ions<br>/<br>&cell<br> cell_dofree='ibrav'<br>/<br>ATOMIC_SPECIES<br> Bi  208.98  Bi.rel-pbe-dn-rrkjus_psl.1.0.0.UPF<br> Se1  78.96  Se.rel-pbe-dn-rrkjus_psl.1.0.0.UPF<br> Se2  78.96  Se.rel-pbe-dn-rrkjus_psl.1.0.0.UPF<br><br>ATOMIC_POSITIONS (alat)<br> Bi   0.3973   0.3973   0.3973  0 0 0<br> Bi   0.6027   0.6027   0.6027  0 0 0<br> Se1   0.0000   0.0000   0.0000  0 0 0<br> Se2   0.2079   0.2079   0.2079  0 0 0<br> Se2   0.7821   0.7821   0.7821  0 0 0<br>K_POINTS (automatic)<br> 8 8 8 0 0 0<br></div><div><br></div><div>&control<br> calculation = 'bands'<br> prefix='bi2se3rel'<br> restart_mode = 'from_scratch'<br> wf_collect=.true.,<br> verbosity='high',<br> outdir= '/home/name/QEoutput'<br> pseudo_dir='/home/name/quantum_espresso/q-e-qe-6.5/pseudo'<br> etot_conv_thr = 1e-5<br> forc_conv_thr = 1e-4<br>/<br>&system<br> ibrav = -5, celldm(1) = 18.6947, celldm(4) = 0.9135, nat = 5, ntyp = 3,<br> ecutwfc = 40, ecutrho = 500,<br> rhombohedral = .true.,<br> noncolin=.true.,lspinorb=.true.,starting_magnetization=0.,<br> nbnd=78,<br> vdw_corr = 'grimme-d2'<br>/<br>&electrons<br> conv_thr = 1.0e-8,<br> diago_full_acc=.true.,<br>/<br>ATOMIC_SPECIES<br> Bi  208.98  Bi.rel-pbe-dn-rrkjus_psl.1.0.0.UPF<br> Se1  78.96  Se.rel-pbe-dn-rrkjus_psl.1.0.0.UPF<br> Se2  78.96  Se.rel-pbe-dn-rrkjus_psl.1.0.0.UPF<br><br>ATOMIC_POSITIONS crystal<br> Bi   0.3973   0.3973   0.3973  0 0 0<br> Bi   0.6027   0.6027   0.6027  0 0 0<br> Se1   1.0000   1.0000   1.0000  0 0 0<br> Se2   0.2079   0.2079   0.2079  0 0 0<br> Se2   0.7821   0.7821   0.7821  0 0 0<br>K_POINTS crystal_b<br>5<br> 0.00000    0.00000    0.00000   20 !gG<br> 0.50000    0.50000    0.50000   20 !Z<br> 0.50000    0.50000   -0.00000   20 !F<br> 0.00000    0.00000    0.00000   20 !gG<br> 0.00000    0.00000   -0.50000   20  !L1<br></div><div><br></div><div>Thank you,</div><div>Varrick Suezaki</div><div>Department of Physics and Astronomy</div><div>University of California, Riverside</div></div>