#------------------------------------------------------------------------------
#$Date: 2008-03-10 08:25:41 +0000 (Mon, 10 Mar 2008) $
#$Revision: 255 $
#$URL: svn://www.crystallography.net/cod/cif/9/9009731.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_9009731
loop_
_publ_author_name
'Kusaka K'
'Ohmasa M'
'Hagiya K'
'Iishi K'
'Haga N'
_publ_section_title
;
 On variety of the Ca coordination in the incommensurate structure of
 synthetic iron-bearing akermanite, Ca2(Mg0.55,Fe0.45)Si2O7
 Note: Sample is synthetic, this is the structure obtained by refining the incommensurate
 structure
;
_journal_name_full               'Mineralogical Journal'
_journal_page_first              47
_journal_page_last               58
_journal_volume                  20
_journal_year                    1998
_chemical_formula_sum            'Ca2 (Mg.554 Fe.446) Si2 O7'
_chemical_name_mineral           Akermanite
_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                   7.8679
_cell_length_b                   7.8679
_cell_length_c                   5.0144
_cell_volume                     310.411
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_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
Ca 0.33070 0.16930 0.50610 1.00000
Mg 0.00000 0.00000 0.00000 0.55400
Fe 0.00000 0.00000 0.00000 0.44600
Si 0.13840 0.36160 0.93830 1.00000
O1 0.00000 0.50000 0.82500 1.00000
O2 0.13900 0.36100 0.25700 1.00000
O3 0.07950 0.18980 0.78910 1.00000
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 0.02007 0.02007 0.00892 0.01035 0.00160 -0.00160
Mg 0.00972 0.00972 0.01210 0.00000 0.00000 0.00000
Fe 0.00972 0.00972 0.01210 0.00000 0.00000 0.00000
Si 0.00847 0.00847 0.00624 0.00220 0.00040 -0.00040
O1 0.04171 0.04171 0.00637 0.03262 0.00000 0.00000
O2 0.03073 0.03073 0.00522 0.01662 -0.00100 0.00100
O3 0.03826 0.01192 0.01261 -0.00909 0.00660 -0.00160