data_global _chemical_name_mineral 'Corundum' loop_ _publ_author_name 'Zachariasen W' _journal_name_full 'Skrifter utgitt av det Norske Videnskaps-Akademi i Oslo' _journal_volume 1928 _journal_year 1928 _journal_page_first 1 _journal_page_last 165 _publ_section_title ; Untersuchungen ueber die Kristallstruktur von Sesquioxyden und Verbindungen ABO3 _cod_database_code 1010951 ; _database_code_amcsd 0017671 _chemical_formula_sum 'Al2 O3' _cell_length_a 5.13 _cell_length_b 5.13 _cell_length_c 5.13 _cell_angle_alpha 55.27 _cell_angle_beta 55.27 _cell_angle_gamma 55.27 _cell_volume 84.969 _exptl_crystal_density_diffrn 3.985 _symmetry_space_group_name_H-M 'R -3 c' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2-x,1/2-z,1/2-y' '-z,-x,-y' '1/2+y,1/2+x,1/2+z' 'y,z,x' '1/2-z,1/2-y,1/2-x' '-x,-y,-z' '1/2+x,1/2+z,1/2+y' 'z,x,y' '1/2-y,1/2-x,1/2-z' '-y,-z,-x' '1/2+z,1/2+y,1/2+x' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z Al1 0.35000 0.35000 0.35000 O1 -0.05000 0.55000 0.25000