[Wien] Why NN program couldn't work for over 16 atoms in a unit cell

[Peter Blaha]

> I encountered problem for a unit cell more than 16 atoms when I ran NN.
> The case.outputnn couldn't complete to read all atom coordinates. I didn't
> compiled program by myself but just used excutable code from WIEN2k. I checked
> the source code of nn.f. Looks like it can acommodate 64 atoms in a unit cell.
> I think there is no any input files error since the NN ran very well when I reduced atoms to 16 for the same file. but the case.outputnn couldn't complete if I just increase one atom in case.str file. I attached case.in(it is not correct since I just want to know the NN output) and case.str files for your checking.

Hi,
nn does not have a limit, at least not for 16 or 64 atoms.

When testing your struct file I get:

Input/Output Error 148: Invalid character

   In Procedure: main program
        At Line: 120

      Statement: Formatted READ
           Unit: 20
   Connected To: TbMnO3.struct
           Form: Formatted
         Access: Sequential
Records Read   : 101
Records Written: 0

Current I/O Buffer:

 ATOM -17: X=0.32620000 Y=0.05100000 Z=0.70390000
    !

And in your struct file I find that the line for the 17th atom is shifted
to the right causing this error.

ATOM -16: X=0.67380000 Y=0.94900000 Z=0.29610000
          MULT= 1          ISPLIT= 8
C 16       NPT=  381  R0=0.00001791 RMT=    1.4500   Z:  6.0
LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
                     0.0000000 1.0000000 0.0000000
                     0.0000000 0.0000000 1.0000000
 ATOM -17: X=0.32620000 Y=0.05100000 Z=0.70390000

You must simply delete the leading blank.


                                      P.Blaha
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Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
Phone: +43-1-58801-15671             FAX: +43-1-58801-15698
Email: blaha at theochem.tuwien.ac.at    WWW: http://info.tuwien.ac.at/theochem/
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