#------------------------------------------------------------------------------
#$Date: 2008-01-26 13:05:32 +0000 (Sat, 26 Jan 2008) $
#$Revision: 19 $
#$URL: svn://www.crystallography.net/cod/cif/9/9000287.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/
#
# All data on this site have been placed in the public domain by the
# contributors.
#
data_9000287
_chemical_name 'Nepheline'
loop_
_publ_author_name
'Simmons W B'
'Peacor D R'
_journal_name_full "American Mineralogist"
_journal_volume 57
_journal_year 1972
_journal_page_first 1711
_journal_page_last 1719
_publ_section_title
;
 Refinement of the crystal structure of a volcanic nepheline
;
_chemical_formula_sum 'Na3 K (Al3.6 Si4.4) O15.999'
_cell_length_a 10.003
_cell_length_b 10.003
_cell_length_c 8.381
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 726.251
_symmetry_space_group_name_H-M 'P 63'
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  'x-y,x,1/2+z'
  '-y,x-y,z'
  '-x,-y,1/2+z'
  '-x+y,-x,z'
  'y,-x+y,1/2+z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
Na   0.99720   0.44320   0.99130   1.00000
K   0.00000   0.00000   0.98930   1.00000
Al1   0.33330   0.66670   0.18770   0.51000
Si1   0.33330   0.66670   0.18770   0.49000
Si2   0.33330   0.66670   0.79900   0.58000
Al2   0.33330   0.66670   0.79900   0.42000
Si3   0.09330   0.33440   0.30900   0.84000
Al3   0.09330   0.33440   0.30900   0.16000
Al4   0.09340   0.33180   0.68240   0.73000
Si4   0.09340   0.33180   0.68240   0.27000
O1   0.33270   0.70240   0.98460   0.33300
O2   0.02690   0.31680   0.49210   1.00000
O3   0.17130   0.52350   0.72100   1.00000
O4   0.16470   0.51080   0.23930   1.00000
O5   0.22580   0.28730   0.30990   1.00000
O6   0.22290   0.26570   0.68920   1.00000