Adding in vacancy positions

[letshin]

Dear all,

Recently I've been working on displaying crystallographic data for gamma Al2O3 and would like to put in vacancy positions of 

(1/2,1/2,1/6)

(1/2,1/2,2/3)

into the model please. I was wondering if there was a function in Vesta that allowed me to do this or if I would have to create the vacancies manually? 

Thank you,

Zhao

[Philip Howie]

Dear Zhao,

In order to do this, you'll have to break the symmetry of the lattice.  Go to the 'Unit Cell' tab of the 'Edit Data' dialogue and click 'Remove Symmetry', at the bottom.  Now when you go to the 'Structure parameters' tab you'll see each atom listed individually and you'll be able to delete the ones you want to create vacancies.

Hope that helps,

Philip

[Nanak]

Hi Letshin,
    I am trying to work out the structure of gamma alumina. Can you give me the coordinates? I understand it is usually drawn with SG 227 (Fd-3m). Any data on the co-ordinates will be quite helpful (also if u have already worked it out, can u post an image of it?).

Thanks in advance.
Nanak.