data_global
_chemical_name_mineral 'Brownmillerite'
loop_
_publ_author_name
'Redhammer G J'
'Tippelt G'
'Roth G'
'Amthauer G'
_journal_name_full 'American Mineralogist'
_journal_volume 89 
_journal_year 2004
_journal_page_first 405
_journal_page_last 420
_publ_section_title
;
 Structural variations in the brownmillerite series Ca2(Fe2-xAlx)O5:
 Single-crystal X-ray diffraction at 25 deg C and high temperature
 X-ray powder diffraction (25 C <= T <= 1000 C)
 Sample: bht120n2
;
_database_code_amcsd 0003440
_chemical_compound_source 'Synthetic'
_chemical_formula_sum 'Ca2 (Fe.922 Al1.078) O5'
_cell_length_a 5.3269
_cell_length_b 14.4687
_cell_length_c 5.5433
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 427.241
_exptl_crystal_density_diffrn      3.743
_symmetry_space_group_name_H-M 'I 2 m b'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,1/2+z'
  'x,1/2+y,-z'
  '1/2+x,+y,1/2-z'
  'x,1/2-y,z'
  '1/2+x,-y,1/2+z'
  'x,-y,-z'
  '1/2+x,1/2-y,1/2-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_U_iso_or_equiv
Ca   0.49140   0.10871   0.02710   1.00000   0.00730
FeM   0.00040   0.00000   0.00000   0.68400   0.00440
AlM   0.00040   0.00000   0.00000   0.31600   0.00440
FeT   0.95260   0.25000   0.92750   0.23800   0.00300
AlT   0.95260   0.25000   0.92750   0.76200   0.00300
O1   0.24810   0.98680   0.25350   1.00000   0.00720
O2   0.02000   0.14370   0.06660   1.00000   0.01010
O3   0.61680   0.25000   0.86100   1.00000   0.00820