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[Deniz Cakir <dcakir@fen.bilkent.edu.tr>]

Hello,
I am trying to calculate elastic constants of a base centered 
orthorhombic cell. My cell is a primitive cell. But abinit has not 
recognize space group and said that this is not a primitive cell . I 
have used following parameters  and certain combinations to implement 
symmetry by hand,  
chkprim 0
spgroup 64
SPGAXOR 1
SPGORIG 1
brvltt 4
my cell parameters are,
acell  1 1 1 Angstrom
rprim    4.9503200068864560   -3.8920480201614130    0.0000000000000000
             4.9503200068864560    3.8920480201614130    0.0000000000000000
             0.0000000000000000    0.0000000000000000    7.8366856996000050
In some cases, abinit has recognized number of symmetry operations. But 
it has given error after symmetry operations have been applied. Error 
messege is following,
symatm : WARNING -
 Trouble finding symmetrically equivalent atoms
 Applying inv of symm number  2 to atom number   1  of typat  1
 gives tratom= -2.1664E-01  2.8336E-01 -5.0000E-01.
 This is further away from every atom in crystal than the allowed 
tolerance.
 The inverse symmetry matrix is -1  0  0
                                 0 -1  0
                                 0  0  1
 and the nonsymmorphic transl. tnons =    0.0000000    0.5000000    
0.5000000
 The nearest coordinate differs by  9.059E-02 -2.414E-02  1.873E-01
 for indsym(nearest atom)=    8
This indicates that when symatm attempts to find atoms symmetrically
 related to a given atom, the nearest candidate is further away than some
 tolerance.  Should check atomic coordinates and symmetry group input data.