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[Dev Sharma <champbond1983@gmail.com>]

Dear   Quan Phung Manh and  Bryce
Same problem, i am facing. My structure is YVO4 , which is I4/mmm but according the output file, it is  space group P2 (#  3); Bravais mP (primitive monocl.) even i have not specified that  chkprim is 0. please guide ,How can i solve this problem ??
 My input file is pasted below
Thanks
Dev

# Data common to the three different datasets

acell 13.451637476  13.451637476  11.885054518   
angdeg  90 90 90 

#Definition of the atom types
ntypat 3          # There r 3 type of atom
znucl 39 23 8          # The keyword "znucl" refers to the atomic number of the
                  # possible type(s) of atom.  (39- Y, 23 -V  and 8-O)
                        
                         
#Definition of the atoms
natom 24          
typat 1 1 1 1 2 2 2 2  3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3        
xangst               
             0.000000000   5.338725356    0.786162553
             3.559150238   1.779575118    3.930812762
             3.559150238   5.338725356    2.358487657
             0.000000000   1.779575118    5.503137866
             0.000000000   1.779575118    2.358487657
             3.559150238   5.338725356    5.503137866
             0.000000000   5.338725356    3.930812762
             3.559150238   1.779575118    0.786162553
             0.000000000   3.090765987    1.262891534
             3.559150238   6.649916224    4.407541744
             3.559150238   4.027534488    4.407541744
             0.000000000   0.468384251    1.262891534
             5.807109607   5.338725356    2.835216639
             4.870341106   1.779575118    5.979866849
             3.559150238   3.090765987    1.881758675
             0.000000000   6.649916224    5.026408885
             0.000000000   4.027534488    5.026408885
             3.559150238   0.468384251    1.881758675
             4.870341106   5.338725356    0.30943357
             5.807109607   1.779575118    3.45408378
             1.311190868   1.779575118    3.45408378
             2.247959369   5.338725356    0.30943357
             2.247959369   1.779575118    5.979866849
             1.311190868   5.338725356    2.835216639

On Sat, Oct 24, 2009 at 8:31 PM, Quan Phung Manh <manhquank9@gmail.com> wrote:

Dear Bryce

I don't know how your full input is. But I think your problem comes from the keyword: chkprim 0. You doubled the cell, then Abinit symmetry finder found that 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. I guess you used this keyword to pass the error. That why you had P1.

Regards.

2009/10/22 <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

--
Quan Phung Manh
Khoa Hoá học - ĐH Khoa học tự nhiên - 19 Lê Thánh Tông Hà Nội