data_global
_chemical_name_mineral 'Ferrosilite'
loop_
_publ_author_name
'Smyth J R'
_journal_name_full 'American Mineralogist'
_journal_volume 58
_journal_year 1973
_journal_page_first 636
_journal_page_last 648
_publ_section_title
;
 An orthopyroxene structure up to 850 C
 T = 280 C
;
_database_code_amcsd 364
_chemical_formula_sum 'Si2 Mg.636 Fe1.331 Ca.032 O6'
_cell_length_a 18.371
_cell_length_b 9.0
_cell_length_c 5.242
_cell_angle_alpha 90.0
_cell_angle_beta 90.0
_cell_angle_gamma 90.0
_cell_volume 866.707
_exptl_crystal_density_diffrn  3.728
_symmetry_space_group_name_H-M 'P b c a'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  'x,1/2-y,1/2+z'
  '-x,1/2+y,1/2-z'
  '1/2-x,1/2+y,z'
  '1/2+x,1/2-y,-z'
  '1/2+x,y,1/2-z'
  '1/2-x,-y,1/2+z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
Sia   0.272  0.3394  0.0542  1.0
Sib   0.4741  0.3358  0.7907  1.0
Mg1   0.3753  0.654  0.8799  0.594
Fe1   0.3753  0.654  0.8799  0.406
Fe2   0.3776  0.4848  0.3738  0.925
Mg2   0.3776  0.4848  0.3738  0.042
Ca2   0.3776  0.4848  0.3738  0.032
O1a   0.1832  0.3376  0.0476  1.0
O2a   0.3116  0.4967  0.0634  1.0
O3a   0.3024  0.2367  -0.1805  1.0
O1b   0.5624  0.3366  0.7867  1.0
O2b   0.4342  0.4845  0.6997  1.0
O3b   0.4477  0.2059  0.5831  1.0
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
Sia   0.00975  0.01387  0.01364  8e-05  0.00078  -0.00048
Sib   0.01265  0.01371  0.01217  0.00067  0.00039  0.00069
Mg1   0.01094  0.01543  0.01132  -0.00067  -0.00185  0.00041
Fe1   0.01094  0.01543  0.01132  -0.00067  -0.00185  0.00041
Fe2   0.01573  0.02048  0.01602  -0.00142  -0.00551  0.00045
Mg2   0.01573  0.02048  0.01602  -0.00142  -0.00551  0.00045
Ca2   0.01573  0.02048  0.01602  -0.00142  -0.00551  0.00045
O1a   0.01231  0.01477  0.01105  -0.00327  -0.00259  -0.00131
O2a   0.01624  0.02003  0.01306  0.00235  0.00161  -0.00674
O3a   0.01214  0.02524  0.02038  -0.00704  -0.0022  0.00574
O1b   0.01522  0.01535  0.01256  -0.00126  -0.00307  -0.00091
O2b   0.01368  0.01609  0.01002  0.00034  0.0059  -0.00535
O3b   0.0094  0.02236  0.01903  -8e-05  -0.00302  -0.00356