[Pw_forum] (no subject)

[GAO Zhe]

According to your input information, nat=48, I think you wanted to make 2x2x2 rutile-TiO2 supercell with a substitutional Nb. However, you setted celldm(1) and ATOMIC_POSITIONS wrong.
You may set celldm(1)=1 and keep CELL_PARAMETERS; or keep celldm(1)=8.7 and set CELL_PARAMETERS as
2.000   0.000   0.000
0.000   2.000   0.000
0.000   0.000   1.288
For ATOMIC_POSITIONS, you may set it as:
ATOMIC_POSITIONS {crystal}
  O   0.1523998693948630   0.1523998693948630   0.0000000000000000
  O   0.3476001306051368   0.3476001306051368   0.0000000000000000
  O   0.0976001306051369   0.4023998693948629   0.2500000000000001
  O   0.4023998693948629   0.0976001306051369   0.2500000000000001
  O   0.6523998693948631   0.1523998693948630   0.0000000000000000
  O   0.8476001306051368   0.3476001306051368   0.0000000000000000
  O   0.5976001306051370   0.4023998693948629   0.2500000000000001
  O   0.9023998693948629   0.0976001306051369   0.2500000000000001
  O   0.1523998693948630   0.6523998693948631   0.0000000000000000
  O   0.3476001306051368   0.8476001306051368   0.0000000000000000
  O   0.0976001306051369   0.9023998693948629   0.2500000000000001
  O   0.4023998693948629   0.5976001306051370   0.2500000000000001
  O   0.6523998693948631   0.6523998693948631   0.0000000000000000
  O   0.8476001306051368   0.8476001306051368   0.0000000000000000
  O   0.5976001306051370   0.9023998693948629   0.2500000000000001
  O   0.9023998693948629   0.5976001306051370   0.2500000000000001
  O   0.1523998693948630   0.1523998693948630   0.5000000000000000
  O   0.3476001306051368   0.3476001306051368   0.5000000000000000
  O   0.0976001306051369   0.4023998693948629   0.7500000000000001
  O   0.4023998693948629   0.0976001306051369   0.7500000000000001
  O   0.6523998693948631   0.1523998693948630   0.5000000000000000
  O   0.8476001306051368   0.3476001306051368   0.5000000000000000
  O   0.5976001306051370   0.4023998693948629   0.7500000000000001
  O   0.9023998693948629   0.0976001306051369   0.7500000000000001
  O   0.1523998693948630   0.6523998693948631   0.5000000000000000
  O   0.3476001306051368   0.8476001306051368   0.5000000000000000
  O   0.0976001306051369   0.9023998693948629   0.7500000000000001
  O   0.4023998693948629   0.5976001306051370   0.7500000000000001
  O   0.6523998693948631   0.6523998693948631   0.5000000000000000
  O   0.8476001306051368   0.8476001306051368   0.5000000000000000
  O   0.5976001306051370   0.9023998693948629   0.7500000000000001
  O   0.9023998693948629   0.5976001306051370   0.7500000000000001
 Ti  -0.0000000000000000  -0.0000000000000000   0.0000000000000000
 Ti   0.2499999999999998   0.2499999999999998   0.2500000000000001
 Ti   0.5000000000000000  -0.0000000000000000   0.0000000000000000
 Ti   0.7499999999999998   0.2499999999999998   0.2500000000000001
 Ti  -0.0000000000000000   0.5000000000000000   0.0000000000000000
 Ti   0.2499999999999998   0.7499999999999998   0.2500000000000001
 Ti   0.5000000000000000   0.5000000000000000   0.0000000000000000
 Ti   0.7499999999999998   0.7499999999999998   0.2500000000000001
 Ti  -0.0000000000000000  -0.0000000000000000   0.5000000000000000
 Ti   0.2499999999999998   0.2499999999999998   0.7500000000000001
 Ti   0.5000000000000000  -0.0000000000000000   0.5000000000000000
 Ti   0.7499999999999998   0.2499999999999998   0.7500000000000001
 Ti  -0.0000000000000000   0.5000000000000000   0.5000000000000000
 Ti   0.2499999999999998   0.7499999999999998   0.7500000000000001
 Ti   0.5000000000000000   0.5000000000000000   0.5000000000000000
 Ti   0.7499999999999998   0.7499999999999998   0.7500000000000001

--
GAO Zhe
CMC Lab, MSE, SNU, Seoul, S.Korea


At 2011-09-07 20:22:30,"Winfred Mulwa" <mulwawinfred at yahoo.com> wrote:

Dear all


       I have tried doing a vc-relax on the attached TiO2 rutile supercell,
the calculations stop after a few minutes without giving any error.

What might be the problem?
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