data_global _chemical_name_mineral 'Brownmillerite' loop_ _publ_author_name 'Colville A' 'Geller S' _journal_name_full 'Acta Crystallographica, Section B' _journal_volume 28 _journal_year 1972 _journal_page_first 3196 _journal_page_last 3200 _publ_section_title ; Crystal structures of Ca2Fe1.43Al0.57O5 and Ca2Fe1.28Al0.72O5 _cod_database_code 1000040 ; _database_code_amcsd 0009431 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'Ca2 (Fe1.4 Al.6) O5' _cell_length_a 5.588 _cell_length_b 14.61 _cell_length_c 5.380 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 439.227 _exptl_crystal_density_diffrn 3.849 _symmetry_space_group_name_H-M 'I b m 2' 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 Ca1 0.02700 0.10840 0.49100 1.00000 Fe1 0.00000 0.00000 0.00000 0.85000 Al1 0.00000 0.00000 0.00000 0.15000 Fe2 0.92930 0.25000 0.95160 0.55000 Al2 0.92930 0.25000 0.95160 0.45000 O1 0.25330 0.98560 0.25200 1.00000 O2 0.06870 0.14290 0.02690 1.00000 O3 0.86680 0.25000 0.61470 1.00000