Space Group Change after creating a defect compound

[Steven]

Sir ,
       To model a defect compound (disordered rocksalt), i used repeat cell . I found that after building the structure with  vacancies involved , the space group changes .
      1. Will this change not affect the results of any calculation ?
     2. If elastic constants are calculated, how to analyse the result if there are more independent elastic constants than the rocksalt structure?

[Anders Blom]

Of course the space group changes - you introduced vacancies.

1) No (well, the results will be different because now you have vacancies)
2) Yes but that is correct, it's not rocksalt anymore