The ABINIT Users Mailing List ( CLOSED )

[<bmeredig@gmail.com>]

Dear Abinit users,

I'm having symmetry issues... I'm working with a distorted fluorite cell that
should have I4/mmm symmetry. When I use these inputs:

typat 1 2 2
xred
0 0 0
0.25 0.25 0.25
0.75 0.75 0.75
acell
1.0 1.0 1.0 angstrom
rprim
0 2.785 2.745
2.785 0 2.745
2.785 2.785 0

The symmetry finder gives me, correctly, I4/mmm. However, when I simply double
the cell along the c direction so:

typat 1 1 2 2 2 2
xred
0 0 0
0 0 0.5
0.25 0.25 0.125
0.25 0.25 0.625
0.75 0.75 0.375
0.75 0.75 0.875
acell
1.0 1.0 1.0 angstrom
rprim
0 2.785 2.745
2.785 0 2.745
5.57 5.57 0

ABINIT then thinks I have P1 (non)symmetry. However, a tool such as FINDSYM at
http://stokes.byu.edu/cgi-bin/iso/findsym.cgi readily verifies that I still in
fact have I4/mmm symmetry. What could be wrong?

Thanks--
Bryce