data_global _chemical_name_mineral 'Boralsilite' loop_ _publ_author_name 'Peacor D R' 'Rouse R C' 'Grew E S' _journal_name_full 'American Mineralogist' _journal_volume 84 _journal_year 1999 _journal_page_first 1152 _journal_page_last 1161 _publ_section_title ; The crystal structure of boralsilite and its relation to a family of boroaluminosilicates, sillimanite, and andalusite ; _database_code_amcsd 0002272 _chemical_formula_sum 'Al8 Si B3 O18.525' _cell_length_a 14.767 _cell_length_b 5.574 _cell_length_c 15.079 _cell_angle_alpha 90 _cell_angle_beta 91.96 _cell_angle_gamma 90 _cell_volume 1240.445 _exptl_crystal_density_diffrn 3.067 _symmetry_space_group_name_H-M 'C 1 2/m 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' '-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 _atom_site_U_iso_or_equiv Al1 0.86873 0.00000 0.33837 1.00000 ? Al2 0.81194 0.00000 0.15838 1.00000 ? Al3 0.57170 0.00000 0.06951 1.00000 ? Al4 0.67697 0.00000 0.34140 1.00000 ? Al5 0.00396 0.74670 0.24322 1.00000 ? Al6 0.25000 0.25000 0.00000 1.00000 ? Al7 0.25000 0.25000 0.50000 1.00000 ? Si 0.42541 0.00000 0.41917 1.00000 ? B1 0.10180 0.00000 0.10090 1.00000 ? B2 0.37740 0.00000 0.11920 1.00000 ? B3 0.13560 0.00000 0.36330 1.00000 ? O1 0.76580 0.00000 0.26710 1.00000 ? O2 0.79650 0.00000 0.43400 1.00000 ? O3 0.92440 0.00000 0.22140 1.00000 ? O4 0.93550 0.73870 0.35730 1.00000 ? O5 0.00000 0.50000 0.50000 1.00000 ? O6 0.32340 0.00000 0.45840 1.00000 ? O7 0.82080 0.71510 0.10630 1.00000 ? O8 0.69730 0.00000 0.06130 1.00000 ? O9 0.06800 0.78430 0.13330 1.00000 ? O10A 0.44440 0.00000 0.04940 0.95000 ? O10B 0.00000 0.50000 0.00000 0.15000 0.03420 O11 0.66780 0.28770 0.39910 1.00000 ? O12 0.57570 0.00000 0.28120 1.00000 ? O13 0.43130 0.00000 0.20050 1.00000 ? O14 0.07670 0.00000 0.29270 1.00000 ? O15 0.83140 0.00000 0.95940 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 Al1 0.00580 0.00380 0.00650 0.00000 0.00040 0.00000 Al2 0.00710 0.00410 0.00400 0.00000 0.00090 0.00000 Al3 0.00590 0.00480 0.00880 0.00000 0.00300 0.00000 Al4 0.00460 0.00380 0.00670 0.00000 0.00020 0.00000 Al5 0.00620 0.00330 0.00680 0.00000 -0.00040 -0.00010 Al6 0.00570 0.00370 0.00550 0.00010 -0.00050 -0.00070 Al7 0.00660 0.00370 0.00510 0.00040 0.00020 0.00090 Si 0.00590 0.00390 0.00630 0.00000 0.00080 0.00000 B1 0.01400 0.00300 0.00800 0.00000 0.00600 0.00000 B2 0.00900 0.00800 0.00900 0.00000 -0.00500 0.00000 B3 0.00900 0.00800 0.00400 0.00000 0.00100 0.00000 O1 0.00550 0.01070 0.00620 0.00000 -0.00080 0.00000 O2 0.00770 0.00460 0.00780 0.00000 0.00160 0.00000 O3 0.00380 0.00420 0.00750 0.00000 -0.00010 0.00000 O4 0.00860 0.00690 0.00860 0.00060 0.00230 0.00130 O5 0.01140 0.01270 0.00990 0.00000 -0.00320 0.00000 O6 0.00720 0.00470 0.00890 0.00000 0.00060 0.00000 O7 0.00770 0.00590 0.00800 0.00010 -0.00270 -0.00090 O8 0.00560 0.00550 0.00780 0.00000 0.00240 0.00000 O9 0.00860 0.00540 0.00820 0.00040 0.00160 0.00010 O10A 0.00870 0.01580 0.01260 0.00000 -0.00110 0.00000 O11 0.00920 0.00640 0.00600 -0.00020 -0.00200 -0.00110 O12 0.00470 0.00590 0.00840 0.00000 -0.00110 0.00000 O13 0.00750 0.00450 0.00940 0.00000 -0.00160 0.00000 O14 0.00680 0.00500 0.00660 0.00000 -0.00130 0.00000 O15 0.00520 0.00440 0.00980 0.00000 0.00020 0.00000