Space groups

Development
1

Hi,
does avogadro have support for space groups when displaying crystal
lattices? I’m looking around for code that can properly decode
lattice space groups like:

_symmetry_space_group_name_H-M ‘P -3’
_symmetry_Int_Tables_number 147
symmetry_cell_setting trigonal
loop
_symmetry_equiv_pos_as_xyz
’+x,+y,+z’
’-y,+x-y,+z’
’-x+y,-x,+z’
’-x,-y,-z’
’+y,-x+y,-z’
’+x-y,+x,-z’

thanks for any pointers,
best,
wes

2

On Sunday 02 August 2009 15:28:28 Wesley Smith wrote:

Hi,
does avogadro have support for space groups when displaying crystal
lattices? I’m looking around for code that can properly decode
lattice space groups like:

_symmetry_space_group_name_H-M ‘P -3’
_symmetry_Int_Tables_number 147
symmetry_cell_setting trigonal
loop
_symmetry_equiv_pos_as_xyz
‘+x,+y,+z’
‘-y,+x-y,+z’
‘-x+y,-x,+z’
‘-x,-y,-z’
‘+y,-x+y,-z’
‘+x-y,+x,-z’

thanks for any pointers,
best,
wes

That looks a lot like a CIF file to me. You can load up a CIF file (Open Babel
handles that), and use the unit cell or super cell builder. I have been
working with someone on visualizing zeolites that are saved as unique atoms in
a CIF file, and use the supercell builder to expand out, rebond and visualize
larger units.

Is that the kind of thing you were looking for?

  • Marcus
3

That looks a lot like a CIF file to me. You can load up a CIF file
(Open Babel
handles that), and use the unit cell or super cell builder. I have
been

What I would personally like, is a box to set the space group in the
unit cell parameter dialog, but that won’t happen for 1.0.

I think we need some sort of “crystallographic builder” where you can
set the space group and fractional coordinates yourself. It’s a minor
thing that I’ll work on for 1.1.

Cheers,
-Geoff