[Pw_forum] symmetry operation # not compatible with FFT grid

[Axel Kohlmeyer]

On Fri, 29 Feb 2008, Subhradip Ghosh wrote:

SG> I am trying to run self-consistent calculations on a heusler structure
SG> with tetragonal distortion i.e. c/a=1.2. In the very beginning I am
SG> getting the following warnings:
SG> 
SG> 
SG>  warning: symmetry operation #  2 not compatible with FFT grid.

please check out the troubleshooting guide:
http://www.quantum-espresso.org/wiki/index.php/Troubleshooting_%28PWscf%29#warning:_.27symmetry_operation_.23_N_not_allowed.27

cheers,
   axel.

SG>    0   1  -1
SG>    1   0  -1
SG>    0   0  -1
SG>      warning: symmetry operation #  3 not compatible with FFT grid.
SG>    0  -1   1
SG>    0  -1   0
SG>    1  -1   0
SG>      warning: symmetry operation #  4 not compatible with FFT grid.
SG>   -1   0   0
SG>   -1   0   1
SG>   -1   1   0
SG>      warning: symmetry operation #  5 not compatible with FFT grid.
SG> 
SG> What could be the cause for this and how to get rid of it? I ran
SG> calculations with c/a=0.9 and c/a=1-the warning didn't ocuur. But it is
SG> coming up with c/a=1 and c/a=1.2.
SG> 
SG> Subhradip
SG> 
SG> ************************************************************************
SG>               Dr. Subhradip Ghosh
SG>               Assistant Professor
SG>               Department of Physics
SG>             Indian Institute of Technology
SG>                Guwahati,Assam-781039
SG>                     India
SG>                E-mail:subhra at iitg.ernet.in
SG>                Phone: +91 361 2582717(O)
SG>                       +91 361 2584717(R)
SG>                 Fax:  +91 361 2582749 (Physics)
SG>                       +91 361 2690762 (General)
SG> ************************************************************************
SG> 
SG> 
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SG> 

-- 
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Axel Kohlmeyer   akohlmey at cmm.chem.upenn.edu   http://www.cmm.upenn.edu
   Center for Molecular Modeling   --   University of Pennsylvania
Department of Chemistry, 231 S.34th Street, Philadelphia, PA 19104-6323
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