ABINIT Discussion Forums

Posted: **Wed Feb 11, 2015 3:38 pm**

Dear users ABINIT
Currently I am trying to study the phase stability in a binary materials Cu3Al type. My problem is that I have a conventional cell and I try to determine the primitive cell except that I do not know the the space group of this structure.
My conventional mesh is of type:

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acell 8.428 24.094 9.864
angdeg 90.0 90.0 83.304
natom 24
ntypat 2
typat 6*1 18*2
xred 
0.500 0.000 0.250
0.111 0.167 0.750
0.722 0.333 0.250
0.000 0.500 0.750
0.611 0.667 0.250
0.222 0.833 0.750
0.000 0.000 0.000
0.000 0.000 0.500
0.500 0.000 0.750
0.611 0.167 0.000
0.611 0.167 0.500
0.111 0.167 0.250
0.222 0.333 0.000
0.222 0.333 0.500
0.722 0.333 0.750
0.500 0.500 0.000
0.500 0.500 0.500
0.000 0.500 0.250
0.111 0.667 0.000
0.111 0.667 0.500
0.611 0.667 0.750
0.722 0.833 0.000
0.722 0.833 0.500
0.222 0.833 0.250

Could you tell me a way to determine the primitive cell and eventually the space group?
When I run the job, I get the following result:

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According to the symmetry finder, the unit cell is
NOT primitive. The multiplicity is 2 .
The use of non-primitive unit cells is allowed
only when the input variable chkprim is 0.
Action : either change your unit cell (rprim or angdeg),
or set chkprim to 0.

Best Regards.

Posted: **Wed Feb 18, 2015 10:47 am**

If you don't care about the cost of the calculation you can add

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chkprim 0

to your input file to not check if the cell is primitive or not.

OR You can use a tool like findsym to get the space group of your cell.
http://stokes.byu.edu/iso/findsym.php

Cheers

ABINIT Discussion Forums

Primitive cell and space group??

Primitive cell and space group?? [SOLVED]

Re: Primitive cell and space group??