<br><div class="gmail_quote"><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Hi, <br>I am doing a test of scf of ideal graphene with tpss pseudopotential.<br>
it crashed with the error  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%<br>     task #         6<br>     from  pzpotrf  : error #        14<br>
      problems computing cholesky decomposition <br> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%<br><br>you can see from the output that the total energy changed from -22 to -2863.<br><br>

<br>iteration #  5     ecut=    40.00 Ry     beta=0.30<br>     Davidson diagonalization with overlap<br>     ethr =  1.00E-02,  avg # of iterations =  1.1<br>     Warning: cannot save meta-gga kinetic terms: not implemented.<br>

<br>     total cpu time spent up to now is      3.41 secs<br><br>     total energy              =     -22.63457069 Ry<br>     Harris-Foulkes estimate   =     -22.97866955 Ry<br>     estimated scf accuracy    <       2.78503926 Ry<br>

<br>     iteration #  6     ecut=    40.00 Ry     beta=0.30<br>     Davidson diagonalization with overlap<br>     ethr =  1.00E-02,  avg # of iterations =  3.6<br>     Warning: cannot save meta-gga kinetic terms: not implemented.<br>

<br>     total cpu time spent up to now is      3.68 secs<br><br>     total energy              =   -2863.69961690 Ry<br>     Harris-Foulkes estimate   =     -22.67770863 Ry<br>     estimated scf accuracy    <       0.06270506 Ry<br>

<br>     iteration #  7     ecut=    40.00 Ry     beta=0.30<br>     Davidson diagonalization with overlap<br>     c_bands:  4 eigenvalues not converged<br>     c_bands:  4 eigenvalues not converged<br><br><br>&CONTROL<br>

                 calculation = 'scf' ,<br>                restart_mode = 'from_scratch' ,<br>                  pseudo_dir = '../pseudo' ,<br>                     outdir  = './',<br>                      prefix = 'GR' , <br>

                      wf_collect=.true.,<br>                    forc_conv_thr = 1.0D-3,<br>                    etot_conv_thr = 1.0D-4,<br>                     tstress = .true. ,<br>                     tprnfor = .true. ,<br>

 /<br> &SYSTEM<br>                       ibrav = 4,<br>                   celldm(1) = 4.601,<br>                   celldm(3) = 5.0,<br>                         nat = 2,<br>                        ntyp = 1,<br>                     ecutwfc = 40 ,<br>

                     ecutrho = 320 ,<br>                 occupations = 'smearing' ,<br>                     degauss = 0.03D0 ,<br>                    smearing = 'cold' ,<br> /<br> &ELECTRONS<br>                 mixing_mode = 'plain' ,<br>

                 mixing_beta = 0.3 ,<br>             diagonalization = 'david',<br>               <br> /<br>ATOMIC_SPECIES<br>    C   12.0107     C.tpss-mt.UPF <br>ATOMIC_POSITIONS alat<br>    C      0.000000000    0.000000000    0.000000000<br>

    C      0.000000000    0.577350269    0.000000000<br>K_POINTS automatic<br> 16 16 1   0 0 0<br><br>so what is wrong? <br></blockquote><div><br>Shu Xu<br>phD of Dept. of Physics<br>NCSU<br>USA <br></div></div><br>