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#$Date: 2008-01-26 15:05:32 +0200 (Sat, 26 Jan 2008) $
#$Revision: 19 $
#$URL: file:///home/coder/svn-repositories/cod/cif/9/9001994.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_9001994
_chemical_name 'Fluoro-eckermannite'
loop_
_publ_author_name
'Oberti R'
'Hawthorne F C'
'Camara F'
'Raudsepp M'
_journal_name_full "American Mineralogist"
_journal_volume 84
_journal_year 1999
_journal_page_first 102
_journal_page_last 111
_publ_section_title
;
 Unusual M3+ cations in synthetic amphiboles with nominal fluoro-eckermannite
 composition: Deviations from stoichiometry and structural effects of the
 cummingtonite component
 Sample: Sc, Na.92Na1.97Mg.03Mg3.95Sc1.05Si8O22F2
;
_chemical_formula_sum 'Si8 Mg4 Sc1.06 Na3.65 O22 F2'
_cell_length_a 9.820
_cell_length_b 18.036
_cell_length_c 5.290
_cell_angle_alpha 90
_cell_angle_beta 103.64
_cell_angle_gamma 90
_cell_volume 910.506
_symmetry_space_group_name_H-M 'C 1 2/m 1'
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  'x,-y,z'
  '1/2+x,1/2-y,z'
  '-x,y,-z'
  '1/2-x,1/2+y,-z'
  '-x,-y,-z'
  '1/2-x,1/2-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_Uiso_or_equiv
Si(1)   0.28270   0.08450   0.29070   1.00000   0.00456
Si(2)   0.28830   0.16950   0.79530   1.00000   0.00545
Mg(1)   0.00000   0.08840   0.50000   1.00000   0.00646
Sc(2)   0.00000   0.18150   0.00000   0.53000   0.00608
Mg(2)   0.00000   0.18150   0.00000   0.47000   0.00608
Mg(3)   0.00000   0.00000   0.00000   1.00000   0.00646
Na(4)   0.00000   0.27600   0.50000   0.97000   0.02546
Mg(4)   0.00000   0.27600   0.50000   0.03000   0.02546
NaA   0.00000   0.50000   0.00000   0.27000   0.02546
NaA(m)   0.04070   0.50000   0.09370   0.52000   0.02951
NaA(2)   0.00000   0.47490   0.00000   0.20000   0.03888
O1   0.11410   0.08460   0.21600   1.00000   0.00595
O2   0.11940   0.16590   0.72650   1.00000   0.00621
F3   0.10120   0.00000   0.70970   1.00000   0.00747
O4   0.36000   0.24830   0.79680   1.00000   0.00988
O5   0.34900   0.12740   0.07830   1.00000   0.00925
O6   0.34450   0.11800   0.57890   1.00000   0.00912
O7   0.34270   0.00000   0.29070   1.00000   0.00899