data_global _chemical_name_mineral 'Mullite' loop_ _publ_author_name 'Fischer R X' 'Schneider H' 'Schmucker M' _journal_name_full 'American Mineralogist' _journal_volume 79 _journal_year 1994 _journal_page_first 983 _journal_page_last 990 _publ_section_title ; Crystal structure of Al-rich mullite ; _database_code_amcsd 0001673 _chemical_formula_sum 'Al2.826 Si.174 O4.588' _cell_length_a 7.7391 _cell_length_b 7.6108 _cell_length_c 2.9180 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 171.872 _exptl_crystal_density_diffrn 2.986 _symmetry_space_group_name_H-M 'P b a m' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2-y,z' '1/2-x,1/2+y,-z' '1/2-x,1/2+y,z' '1/2+x,1/2-y,-z' 'x,y,-z' '-x,-y,z' '-x,-y,-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 Al 0.00000 0.00000 0.00000 1.00000 0.02444 AlT 0.14790 0.33170 0.50000 0.50000 0.00203 SiT 0.14790 0.33170 0.50000 0.08700 0.00203 Al* 0.25900 0.22030 0.50000 0.29400 0.00633 Al** 0.33500 0.10300 0.50000 0.11900 0.03800 Oab 0.35390 0.42090 0.50000 1.00000 0.02406 Oc 0.47000 0.02800 0.50000 0.29400 0.05319 Od 0.13360 0.21640 0.00000 1.00000 0.03673