data_global _chemical_name_mineral 'Corundum' loop_ _publ_author_name 'Ishizawa N' 'Miyata T' 'Minato I' 'Marumo F' 'Iwai S' _journal_name_full 'Acta Crystallographica, Section B' _journal_volume 36 _journal_year 1980 _journal_page_first 228 _journal_page_last 230 _publ_section_title ; A structural investigation of alpha-Al2O3 at 2170 K T = 300 K ; _database_code_amcsd 0009699 _chemical_formula_sum 'Al2 O3' _cell_length_a 4.754 _cell_length_b 4.754 _cell_length_c 12.99 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _cell_volume 254.248 _exptl_crystal_density_diffrn 3.996 _symmetry_space_group_name_H-M 'R -3 c' loop_ _space_group_symop_operation_xyz 'x,y,z' '2/3+x,1/3+y,1/3+z' '1/3+x,2/3+y,2/3+z' 'x,x-y,1/2+z' '2/3+x,1/3+x-y,5/6+z' '1/3+x,2/3+x-y,1/6+z' 'y,x,1/2-z' '2/3+y,1/3+x,5/6-z' '1/3+y,2/3+x,1/6-z' '-x+y,y,1/2+z' '2/3-x+y,1/3+y,5/6+z' '1/3-x+y,2/3+y,1/6+z' '-x,-x+y,1/2-z' '2/3-x,1/3-x+y,5/6-z' '1/3-x,2/3-x+y,1/6-z' '-y,-x,1/2+z' '2/3-y,1/3-x,5/6+z' '1/3-y,2/3-x,1/6+z' 'x-y,-y,1/2-z' '2/3+x-y,1/3-y,5/6-z' '1/3+x-y,2/3-y,1/6-z' 'y,-x+y,-z' '2/3+y,1/3-x+y,1/3-z' '1/3+y,2/3-x+y,2/3-z' '-x+y,-x,z' '2/3-x+y,1/3-x,1/3+z' '1/3-x+y,2/3-x,2/3+z' '-x,-y,-z' '2/3-x,1/3-y,1/3-z' '1/3-x,2/3-y,2/3-z' '-y,x-y,z' '2/3-y,1/3+x-y,1/3+z' '1/3-y,2/3+x-y,2/3+z' 'x-y,x,-z' '2/3+x-y,1/3+x,1/3-z' '1/3+x-y,2/3+x,2/3-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv Al 0.00000 0.00000 0.35228 0.00405 O 0.30640 0.00000 0.25000 0.00418 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 Al 0.00510 0.00510 0.00190 0.00255 0.00000 0.00000 O 0.00510 0.00510 0.00250 0.00255 0.00035 0.00070