Hi, 
 
I noticed that sometimes converged DFT calculations give the Kohn-Sham orbitals (which are printed right after the converged energy) in a funny order. Around the Fermi energy, the orbitals are not ordered with increasing energy such that some orbitals are said to be occupied when in fact they shouldn't be. For example : 
 
Vector  835  Occ=2.000000D+00  E=-1.725603D-01 
             MO Center=  4.1D-01,  7.7D-01,  1.2D+00, r^2= 3.1D+01 
  Bfn.  Coefficient  Atom+Function         Bfn.  Coefficient  Atom+Function 
 ----- ------------  ---------------      ----- ------------  --------------- 
 2155      0.290222  203 Pd dyz           1697     -0.287172  184 Pd dxz 
 1435     -0.285856  173 Pd dyz           2225      0.280435  206 Pd dxz 
 1721     -0.259931  185 Pd dxz           2177      0.241332  204 Pd dxz 
 1745     -0.234405  186 Pd dxz           1673     -0.232804  183 Pd dxz 
 2035      0.220113  198 Pd dyz           2032     -0.213596  198 Pd dxy 
 
 
Vector  836  Occ=2.000000D+00  E=-1.708588D-01 
             MO Center=  1.0D+00, -4.2D-01,  1.1D+00, r^2= 3.1D+01 
  Bfn.  Coefficient  Atom+Function         Bfn.  Coefficient  Atom+Function 
 ----- ------------  ---------------      ----- ------------  --------------- 
 1502     -0.206055  176 Pd pz            1915      0.198638  193 Pd dyz 
 1645      0.194995  182 Pd py            1315     -0.191369  168 Pd dyz 
 1193      0.186496  163 Pd dxz           1888      0.174989  192 Pd dxy 
 1478      0.166567  175 Pd pz            2297     -0.160579  209 Pd dxz 
 1455     -0.158688  174 Pd dxx           1699     -0.158116  184 Pd dyz 
 
 
Vector  837  Occ=0.000000D+00  E=-1.737251D-01 
             MO Center=  1.2D+00, -2.3D-01,  9.2D-01, r^2= 2.7D+01 
  Bfn.  Coefficient  Atom+Function         Bfn.  Coefficient  Atom+Function 
 ----- ------------  ---------------      ----- ------------  --------------- 
 2032     -0.243681  198 Pd dxy           1384      0.239949  171 Pd dxy 
 1336     -0.235336  169 Pd dxy           1624     -0.229898  181 Pd dxy 
 1192      0.195941  163 Pd dxy           1460     -0.178903  174 Pd dzz 
 2176      0.178709  204 Pd dxy           1241      0.178167  165 Pd dxz 
 1408     -0.177786  172 Pd dxy           1506     -0.171399  176 Pd dyy 
 
 
Vector  838  Occ=0.000000D+00  E=-1.722297D-01 
             MO Center=  8.4D-01, -9.0D-01,  1.1D+00, r^2= 2.8D+01 
  Bfn.  Coefficient  Atom+Function         Bfn.  Coefficient  Atom+Function 
 ----- ------------  ---------------      ----- ------------  --------------- 
 1433      0.224043  173 Pd dxz           1792     -0.204859  188 Pd dxy 
 1264      0.199807  166 Pd dxy           1432     -0.196589  173 Pd dxy 
 1673     -0.180613  183 Pd dxz           1480      0.174413  175 Pd dxy 
 1555     -0.169257  178 Pd dyz           2177      0.166209  204 Pd dxz 
 1815     -0.158712  189 Pd dxx           1697     -0.156071  184 Pd dxz 
 
 
Is there a reason for this? Couldn't this affect other values calculated from the converged density since it comprises orbitals that shouldn't be occupied in reality? 
 
Thanks, 
 
Chloe
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