data_global _chemical_name_mineral 'Celsian' loop_ _publ_author_name 'Griffen D T' 'Ribbe P H' _journal_name_full 'American Mineralogist' _journal_volume 61 _journal_year 1976 _journal_page_first 414 _journal_page_last 418 _publ_section_title ; Refinement of the crystal structure of celsian ; _database_code_amcsd 0000519 _chemical_formula_sum 'Ba (Al2 Si2) O8' _cell_length_a 8.622 _cell_length_b 13.078 _cell_length_c 14.411 _cell_angle_alpha 90 _cell_angle_beta 115.1 _cell_angle_gamma 90 _cell_volume 1471.516 _exptl_crystal_density_diffrn 3.389 _symmetry_space_group_name_H-M 'I 1 2/c 1' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2+y,1/2+z' 'x,-y,1/2+z' '1/2+x,1/2-y,+z' '-x,y,1/2-z' '1/2-x,1/2+y,-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 Ba1 0.28270 0.00000 0.06530 1.00000 Al1 0.00960 0.18200 0.11030 0.50000 Si1 0.00960 0.18200 0.11030 0.50000 Al2 0.00760 0.18300 0.61480 0.50000 Si2 0.00760 0.18300 0.61480 0.50000 Al3 0.70540 0.12140 0.17300 0.50000 Si3 0.70540 0.12140 0.17300 0.50000 Al4 0.70190 0.11630 0.67430 0.50000 Si4 0.70190 0.11630 0.67430 0.50000 O1 0.00050 0.13770 -0.00020 1.00000 O2 0.62060 -0.00030 0.14380 1.00000 O3 0.83490 0.13680 0.11190 1.00000 O4 0.81980 0.13700 0.61360 1.00000 O5 0.02200 0.30620 0.12100 1.00000 O6 0.02930 0.31200 0.63120 1.00000 O7 0.18360 0.12960 0.19580 1.00000 O8 0.19000 0.12310 0.70170 1.00000 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 Ba1 0.00865 0.01213 0.01639 -0.00052 0.00361 -0.00086 Al1 0.00865 0.00780 0.01035 -0.00052 0.00413 -0.00086 Si1 0.00865 0.00780 0.01035 -0.00052 0.00413 -0.00086 Al2 0.00401 0.00607 0.00690 -0.00207 0.00103 0.00000 Si2 0.00401 0.00607 0.00690 -0.00207 0.00103 0.00000 Al3 0.00679 0.00347 0.00777 0.00155 0.00258 0.00086 Si3 0.00679 0.00347 0.00777 0.00155 0.00258 0.00086 Al4 0.00494 0.00607 0.00863 -0.00052 0.00206 0.00086 Si4 0.00494 0.00607 0.00863 -0.00052 0.00206 0.00086 O1 0.01452 0.00433 0.00690 -0.00259 0.00310 0.00000 O2 0.00957 0.00173 0.01898 0.00414 0.00258 0.00346 O3 0.01977 0.01300 0.02330 -0.00569 0.01136 -0.00173 O4 0.01204 0.00780 0.01380 0.00207 0.00206 -0.00086 O5 0.01699 0.00780 0.01898 -0.00155 0.00619 0.00086 O6 0.00741 0.01646 0.01898 -0.00052 0.00826 0.00346 O7 0.01174 0.01646 0.01467 -0.00103 0.00310 -0.00259 O8 0.01266 0.01906 0.01380 0.00414 0.00619 0.00259