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#$Date: 2013-05-05 17:21:46 +0300 (Sun, 05 May 2013) $
#$Revision: 85285 $
#$URL: file:///home/coder/svn-repositories/cod/cif/9/00/61/9006116.cif $
#------------------------------------------------------------------------------
#
# 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_9006116
loop_
_publ_author_name
'Swainson, I. P.'
'Dove, M. T.'
'Schmahl, W. W.'
'Putnis, A.'
_publ_section_title
;
 Neutron powder diffraction study of the akermanite-gehlenite
 solid solution series
 Sample: 100% Ak
;
_journal_name_full               'Physics and Chemistry of Minerals'
_journal_page_first              185
_journal_page_last               195
_journal_volume                  19
_journal_year                    1992
_chemical_formula_sum            'Ca2 Mg0.96 O7 Si2'
_chemical_name_mineral           Akermanite
_space_group_IT_number           113
_symmetry_space_group_name_Hall  'P -4 2ab'
_symmetry_space_group_name_H-M   'P -4 21 m'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_length_a                   7.8288
_cell_length_b                   7.8288
_cell_length_c                   5.0052
_cell_volume                     306.769
_exptl_crystal_density_diffrn    2.941
_[local]_cod_chemical_formula_sum_orig 'Ca2 Mg.96 Si2 O7'
_cod_database_code               9006116
loop_
_symmetry_equiv_pos_as_xyz
x,y,z
1/2-y,1/2-x,z
y,-x,-z
1/2-x,1/2+y,-z
-x,-y,z
1/2+y,1/2+x,z
-y,x,-z
1/2+x,1/2-y,-z
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
Ca 0.08321 0.08321 0.00800 0.03571 -0.01112 -0.01112
MgT1 0.04564 0.04564 0.02005 0.00000 0.00000 0.00000
SiT2 0.01490 0.01490 -0.00025 0.00155 -0.00298 -0.00298
O1 0.07700 0.07700 0.00368 -0.06614 0.00000 0.00000
O2 0.07669 0.00000 0.00508 0.00000 0.02164 0.02164
O3 0.12389 0.03384 0.01599 -0.02515 0.01668 -0.00854
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
Ca 0.33200 0.16800 0.50500 1.00000
MgT1 0.00000 0.00000 0.00000 0.96000
SiT2 0.13950 0.36050 0.93340 1.00000
O1 0.50000 0.00000 0.17750 1.00000
O2 0.14090 0.35910 0.25470 1.00000
O3 0.08160 0.18700 0.78790 1.00000