ABINIT Discussion Forums

I pulled the following info from ICSD:
PbO
sp group P4/nmm S (129)

Pb is in wyckoff pos 2c (0.25 0.25 0.2385); O is in wyckoff pos. 2a (0.75 0.25 0

I plug the info into ABINIT and run.... but the job fails as I am told:
Largest error (above) is so large (0.01) that either input atomic coordinates (xred)
are wrong or space group symmetry data is wrong.


Here is the relative code (I think) of the input file:
Note : I have tried this with and without chkprim = 0. and have tried angdeg rather than rprim in other attempts as well.

chkprim 0
occopt 1

acell 3.947 3.947 4.988 Angstroms #litharge
rprim 1.0 0.0 0.0
0.0 1.0 0.0
0.0 0.0 1.0
#angdeg 90 90 90
#Definition of the atom types
ntypat 2
znucl 8 82
natom 4
nband 32
typat 2*1 2*2
xred
0.75 0.25 0.0
0.25 0.75 0.0
0.25 0.25 0.2385
0.75 0.75 0.7615

(I have also tried -0.2385 instead of 0.7615 .... to no avail.)

Any ideas on what I am doing wrong?

Dear brehmj:

These are just some wild guesses:

1) Do you have the line "spgroup 129" in your input file?

2) Are you using "brvltt -1", which says that you are using the coordinates of the conventional unit cell from the ICSD instead of the primitive cell that ABINIT uses internally?

3) Does it make a difference if you use the keyword "Angstrom" with acell, instead of "Angstroms"?

Best,
Kale