data_global _chemical_name_mineral 'Talc' loop_ _publ_author_name 'Perdikatsis B' 'Burzlaff H' _journal_name_full 'Zeitschrift fur Kristallographie' _journal_volume 156 _journal_year 1981 _journal_page_first 177 _journal_page_last 186 _publ_section_title ; Strukturverfeinerung am talk Mg3[(OH)2Si4O10] ; _database_code_amcsd 0010839 _chemical_compound_source 'Harford County, Maryland, USA' _chemical_formula_sum 'Si4 Mg3 O12 H2' _cell_length_a 5.290 _cell_length_b 9.173 _cell_length_c 9.460 _cell_angle_alpha 90.46 _cell_angle_beta 98.68 _cell_angle_gamma 90.09 _cell_volume 453.774 _exptl_crystal_density_diffrn 2.776 _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_U_iso_or_equiv Si1 0.24527 0.50259 0.29093 ? Si2 0.24590 0.83587 0.29108 ? Mg1 0.00000 0.00000 0.00000 ? Mg2 0.50012 0.83332 0.99994 ? O1 0.19910 0.83440 0.11760 ? O2 0.69700 0.66740 0.11260 ? O3 0.19800 0.50120 0.11760 ? O4 0.01990 0.92870 0.34810 ? O5 0.52020 0.91090 0.34940 ? O6 0.24290 0.66990 0.34840 ? H 0.71900 0.66900 0.20300 0.00760 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 Si1 0.00870 0.00740 0.00950 0.00020 0.00140 0.00000 Si2 0.00860 0.00740 0.00970 0.00030 0.00190 -0.00030 Mg1 0.00760 0.00690 0.00970 0.00010 0.00170 -0.00010 Mg2 0.00780 0.00690 0.01010 0.00000 0.00150 -0.00040 O1 0.01000 0.00940 0.01060 0.00000 0.00170 -0.00010 O2 0.01210 0.01020 0.01100 0.00050 0.00170 -0.00010 O3 0.01030 0.00940 0.00970 0.00000 0.00120 0.00000 O4 0.01040 0.01360 0.01330 0.00440 0.00150 -0.00100 O5 0.01120 0.01410 0.01240 -0.00320 0.00220 0.00000 O6 0.01620 0.00850 0.01200 0.00020 0.00240 0.00020