data_global _chemical_name_mineral 'Anorthite' loop_ _publ_author_name 'Wenk H R' 'Joswig W' 'Tagai T' 'Korekawa M' 'Smith B K' _journal_name_full 'American Mineralogist' _journal_volume 65 _journal_year 1980 _journal_page_first 81 _journal_page_last 95 _publ_section_title ; The average structure of An 62-66 labradorite Note: studied with neutrons ; _database_code_amcsd 0019663 _chemical_compound_source 'Surtsey, Iceland' _chemical_formula_sum 'Ca.325 Na.16 (Si1.19 Al.81) O4' _cell_length_a 8.1736 _cell_length_b 12.8736 _cell_length_c 7.1022 _cell_angle_alpha 93.462 _cell_angle_beta 116.054 _cell_angle_gamma 90.475 _cell_volume 669.647 _exptl_crystal_density_diffrn 2.698 _symmetry_space_group_name_H-M 'C -1' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2+y,z' '-x,-y,-z' '1/2-x,1/2-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy Ca1 0.26660 0.98700 0.16200 0.32500 Na1 0.26660 0.98700 0.16200 0.16000 Ca2 0.27330 0.03090 0.09500 0.32500 Na2 0.27330 0.03090 0.09500 0.16000 Si1 0.00620 0.16320 0.21530 0.59500 Al1 0.00620 0.16320 0.21530 0.40500 Si2 0.00260 0.81630 0.23060 0.59500 Al2 0.00260 0.81630 0.23060 0.40500 Si3 0.68480 0.10880 0.31770 0.59500 Al3 0.68480 0.10880 0.31770 0.40500 Si4 0.68060 0.87900 0.35710 0.59500 Al4 0.68060 0.87900 0.35170 0.40500 Oa1 0.00390 0.12900 0.98080 1.00000 Oa2 0.57990 0.99120 0.27860 1.00000 Obo 0.81300 0.10360 0.18920 1.00000 Obm 0.81580 0.85300 0.24440 1.00000 Oco 0.01430 0.28950 0.28170 1.00000 Ocm 0.01220 0.68660 0.21300 1.00000 Odo 0.19720 0.10740 0.38160 1.00000 Odm 0.19020 0.86600 0.42930 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 Ca1 0.01664 0.08269 0.03693 -0.01146 0.01372 -0.03022 Na1 0.01664 0.08269 0.03693 -0.01146 0.01372 -0.03022 Ca2 0.00573 0.02589 0.02093 0.00859 0.00284 -0.00166 Na2 0.00573 0.02589 0.02093 0.00859 0.00284 -0.00166 Si1 0.01009 0.01503 0.01580 0.00000 0.00591 0.00166 Al1 0.01009 0.01503 0.01580 0.00000 0.00591 0.00166 Si2 0.01146 0.01671 0.01539 0.00573 0.00757 0.00124 Al2 0.01146 0.01671 0.01539 0.00573 0.00757 0.00124 Si3 0.00927 0.01253 0.01826 0.00239 0.00686 0.00083 Al3 0.00927 0.01253 0.01826 0.00239 0.00686 0.00083 Si4 0.00873 0.01086 0.01949 0.00143 0.00804 0.00248 Al4 0.00873 0.01086 0.01949 0.00143 0.00804 0.00248 Oa1 0.02946 0.02840 0.02339 0.00477 0.01680 0.00455 Oa2 0.01282 0.01587 0.02565 0.00191 0.00828 0.00373 Obo 0.02182 0.02172 0.03529 -0.00143 0.01798 -0.00041 Obm 0.02182 0.02840 0.04843 0.00525 0.02295 -0.00166 Oco 0.01882 0.02339 0.02996 -0.00286 0.01207 0.00248 Ocm 0.01882 0.02422 0.02380 0.00764 0.00639 -0.00124 Odo 0.01882 0.02255 0.02319 0.00286 0.00591 0.00248 Odm 0.01964 0.02673 0.03037 0.00334 0.00308 -0.00207