<div dir="ltr">Hello everyone,<div><br></div><div>Greetings.</div><div><br></div><div>I am facing the following error while trying to obtain the "Hubbard-U" parameter for Zn in ZnO through linear response theory using hp.x.</div><div><br></div><div><font face="arial narrow, sans-serif"> WARNING: The Fermi energy shift is too big!<br>      This may happen in two cases:<br>      1. The DOS at the Fermi level is too small:<br>         DOS(E_Fermi) =   -0.1639E-79<br>         This means that most likely the system has a gap,<br>         and hence it should NOT be treated as a metal<br>         (otherwise numerical instabilities will appear).<br>      2. Numerical instabilities due to too low cutoff<br>         for hard pseudopotentials.<br><br>      Stopping...<br>STOP 1</font><br></div><div><br></div><div><br></div><div>The scf input file is as follows:</div><div>=======================================================<br clear="all"><div><font face="arial narrow, sans-serif">&control<br>    calculation = 'scf',<br>    prefix='zno',<br>    pseudo_dir = 'D:/Data/samir/qe/pseudo',<br>    outdir='D:/Data/samir/qe/ZnO/hp/tmp'<br>/<br>&system    <br>  ibrav = 4, nat=4, ntyp= 2, a = 3.2494, c = 5.2038<br>  ecutwfc = 60, ecutrho = 300<br>  occupations = 'smearing', smearing = 'mv', degauss=0.001<br>  lda_plus_U=.TRUE.<br>  lda_plus_U_kind = 0,<br>  U_projection_type = 'ortho-atomic'<br>  Hubbard_U(1)=1.d-10<br>/<br><br>&ELECTRONS<br>  mixing_mode='plain'<br>  mixing_beta = 0.7,<br>  conv_thr =  1.0d-10,<br>/<br><br>ATOMIC_SPECIES<br>Zn     65.39000  Zn.pbesol-dnl-kjpaw_psl.1.0.0.UPF<br>O      15.99940  O.pbesol-n-kjpaw_psl.1.0.0.UPF<br><br>ATO&control</font></div><font face="arial narrow, sans-serif">    calculation = 'scf',<br>    prefix='zno',<br>    pseudo_dir = 'D:/Data/samir/qe/pseudo',<br>    outdir='D:/Data/samir/qe/ZnO/hp/tmp'<br>/<br>&system    <br>  ibrav = 4, nat=4, ntyp= 2, a = 3.2494, c = 5.2038<br>  ecutwfc = 60, ecutrho = 300<br>  occupations = 'smearing', smearing = 'mv', degauss=0.001<br>  lda_plus_U=.TRUE.<br>  lda_plus_U_kind = 0,<br>  U_projection_type = 'ortho-atomic'<br>  Hubbard_U(1)=1.d-10<br>/<br><br>&ELECTRONS<br>  mixing_mode='plain'<br>  mixing_beta = 0.7,<br>  conv_thr =  1.0d-10,<br>/<br><br>ATOMIC_SPECIES<br>Zn     65.39000  Zn.pbesol-dnl-kjpaw_psl.1.0.0.UPF<br>O      15.99940  O.pbesol-n-kjpaw_psl.1.0.0.UPF<br><br>ATOMIC_POSITIONS {angstrom}<br>Zn     -0.000016   1.876051   0.000000<br>Zn      1.624700   0.938040   2.601900<br>O      -0.000016   1.876051   1.988372<br>O       1.624700   0.938040   4.590272<br><br>K_POINTS {automatic}<br> 8 8 4  0 0 0</font></div><div>=================================================================<br><div><br></div><div>Can anybody suggest any solution to this?</div><div><br></div><div>Thank you,</div><div>Best wishes</div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr">Samir Ranjan Meher<div>Assistant Professor</div><div>Department of Physics</div><div>School of Advanced Sciences</div><div>Vellore Institute of Technology, Vellore</div><div>Tamilnadu- 632014</div><div>India</div></div></div></div></div></div></div>