[Wien] Space group 185 HoMnO3

[Gerhard Fecher]

partially this is not a problem of Wien2k but of the programs from Crystal Impact
that give the numbers only with 4 digit. I checked, the change of the numerical Format
of Windows does not effect that, different from other programs that make cif Files and depend on such settings.
I guess the easiest thing is to use an editor and search/replace for the too short values

Ciao
Gerhard

====================================
Dr. Gerhard H. Fecher
Institut of Inorganic and Analytical Chemistry
Johannes Gutenberg - University
55099 Mainz
________________________________________
Von: wien-bounces at zeus.theochem.tuwien.ac.at [wien-bounces at zeus.theochem.tuwien.ac.at] im Auftrag von Peter Blaha [pblaha at theochem.tuwien.ac.at]
Gesendet: Dienstag, 12. Januar 2010 20:32
An: A Mailing list for WIEN2k users
Betreff: Re: [Wien] Space group 185 HoMnO3

scan_cif.f even has a "patch" for inaccurate positions and
checks if it should be 1/6, 1/3,...:

      if (f1.and.sseting.eq.'hexagonal') then
         small=2.0d-5
         do i=1,nat
            do j=1,2
               do jfract=1,5
                  fract=jfract/6.d0
                  if (abs(x(j,i)-fract).lt.small) x(j,i)=fract
                  if (abs(x(j,i)+fract).lt.small) x(j,i)=-fract

However, at present it requires a precision of 2.d-5 and this is not
fulfilled when x=0.3333 only.

It is trivial to change and I'll do it, but:  what if you have a cif
file for a structure with a small distortion ??



John Rundgren schrieb:
> Dear All,
> When w2web is applied to HoMnO3.cif (space group 185, 30 atoms/UC), it
> generates HoMnO3.struct (46 atoms/UC), see Attachments. The .struct
> entries are,
> O1 MULT=2
> O2      12 (4 are correct, the rest are repetitions)
> O3      6
> O4      6
> Mn      6
> Ho1     2
> Ho2     12 (4 are correct, the rest are repetitions).
>
> As a consequence, CrysDen is embarrassed and goes terribly slow. When I
> clean up HoMnO3.struct manually, XCrysden is quick as usual.
>
> However, when I make "initialize calc.", w2web goes back to the
> incorrect structure. It starts calculating NN distances between Ho2 and
> itself, which are, of course, equal to zero. Stop.
>
> How can one make w2web understand HoMno3.cif ?
> Thanks in advance,
> John
>
>
>
> ------------------------------------------------------------------------
>
> _______________________________________________
> Wien mailing list
> Wien at zeus.theochem.tuwien.ac.at
> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
_______________________________________________
Wien mailing list
Wien at zeus.theochem.tuwien.ac.at
http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien