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#$Date: 2010-06-10 18:11:07 +0300 (Thu, 10 Jun 2010) $
#$Revision: 1210 $
#$URL: file:///home/coder/svn-repositories/cod/cif/9/9002908.cif $
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#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/. The original data for this entry
# were provided the American Mineralogist Crystal Structure Database,
# http://rruff.geo.arizona.edu/AMS/amcsd.php
#
# The file may be used within the scientific community so long as
# proper attribution is given to the journal article from which the
# data were obtained.
#
data_9002908
loop_
_publ_author_name
'Thompson, R. M.'
'Downs, R. T.'
_publ_section_title
;
 Model pyroxenes I: Ideal pyroxene topologies
 Pyroxene #2 based on stacking sequence ABAC. Ideal analogue of  protopyroxene,
 high-P protopyroxene.
 Note: Atoms Mg, Si, and O are assigned to atomic positions just for convenience.
;
_journal_name_full               'American Mineralogist'
_journal_page_first              653
_journal_page_last               666
_journal_volume                  88
_journal_year                    2003
_chemical_formula_sum            'Mg O3 Si'
_chemical_name_mineral           Pyroxene-ideal
_symmetry_space_group_name_H-M   'P 21 c n'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_length_a                   6.53197264742
_cell_length_b                   6
_cell_length_c                   3.46410161514
_cell_volume                     135.765
_exptl_crystal_density_diffrn    9.823
_[local]_cod_chemical_formula_sum_orig 'Mg Si O3'
_cod_original_cell_volume        135.764
_cod_database_code               9002908
_amcsd_database_code             AMCSD#0002996
loop_
_symmetry_equiv_pos_as_xyz
x,y,z
x,-y,1/2+z
1/2+x,1/2+y,1/2-z
1/2+x,1/2-y,-z
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
Mg1 0.00000 0.08333 0.66667
Mg2 0.00000 0.25000 0.16667
SiA 0.68750 0.91667 0.83333
SiB 0.31250 0.08333 0.00000
O1A 0.87500 0.91667 0.83333
O1B 0.12500 0.08333 0.00000
O2A 0.62500 0.75000 0.00000
O2B 0.37500 0.25000 0.16667
O3A 0.62500 0.91667 0.50000
O3B 0.37500 0.91667 0.16667