ABINIT Discussion Forums

Hi Dear
I am trying to optimize the lattice parameters for Lu2SiO5.
The input file is attached.
The error is:
chkprimit : ERROR -
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.
Najmeh

Dear Najmeh,
It means that the definition of your cell does not correspond to the unit cell (it is a multiple of it). You can keep running with this cell by adding the input flag chkprim 0 as specified in the message or you have to find the real unit cell of this crystal (the FINDYM software of the ISOTROPY suite can do that for example).
Best wishes,
Eric

Thanks for your answer. my problem is solved.

best regards,
Najmeh