Dear Professor and everyone,<br>     I  have successfully run the scf calculation for a (6,6) cnt, and get converged. Thanks for all your advice. Now my boss want me to add a copper atom in it, and do more calculations. I added one, but the copper atom cannot show in xcrysden, although again show in .xyz files. I don't know what the problem is , and I don't know if my script is right for a cnt+ copper calculation, may anyone have a look at it?At least I need to find the copper atom out first. <br>
<br>        &CONTROL<br>                 calculation = 'scf' ,<br>                restart_mode = 'from_scratch' ,<br>                       prefix = 'cnt' ,<br> /<br> &SYSTEM<br>                       ibrav = 6,<br>
                   celldm(1) = 21.764541128,celldm(3)=0.213765379<br>                         nat = 25,<br>                        ntyp = 2,<br>                     ecutwfc = 75 ,<br> /<br> &ELECTRONS<br>                    conv_thr = 1.0d-8 ,<br>
                 mixing_beta = 0.7 ,<br> /<br>ATOMIC_SPECIES<br>    C   12.01100  C.pz-vbc.UPF <br>    Cu  63.55     Cu.pz-d-rrkjus.UPF<br><br>ATOMIC_POSITIONS angstrom<br>  C        4.085165    -0.000000    -1.231010<br>
  C        3.838021     1.399343    -1.231010<br>  C        3.537856     2.042582     0.000000<br>  C        2.624152     3.130877     0.000000<br>  C        2.042582     3.537856    -1.231010<br>  C        0.707144     4.023496    -1.231010<br>
  C        0.000000     4.085165     0.000000<br>  C       -1.399343     3.838021     0.000000<br>  C       -2.042582     3.537856    -1.231010<br>  C       -3.130877     2.624152    -1.231010<br>  C       -3.537856     2.042582     0.000000<br>
  C       -4.023496     0.707144     0.000000<br>  C       -4.085165     0.000000    -1.231010<br>  C       -3.838021    -1.399343    -1.231010<br>  C       -3.537856    -2.042582     0.000000<br>  C       -2.624152    -3.130877     0.000000<br>
  C       -2.042582    -3.537856    -1.231010<br>  C       -0.707144    -4.023496    -1.231010<br>  C       -0.000000    -4.085165     0.000000<br>  C        1.399343    -3.838021     0.000000<br>  C        2.042582    -3.537856    -1.231010<br>
  C        3.130877    -2.624152    -1.231010<br>  C        3.537856    -2.042582     0.000000<br>  C        4.023496    -0.707144     0.000000<br>  Cu       0            0            0<br><br>K_POINTS automatic <br>    1 1 5 0 0 0<br>
<br> <br>Best regards.<br><br>Sincerely,<br>Chengyu Yang<br><br> <br>