data_global _chemical_name_mineral 'Norbergite' loop_ _publ_author_name 'Taylor W' 'West J' _journal_name_full 'Zeitschrift fur Kristallographie' _journal_volume 70 _journal_year 1929 _journal_page_first 461 _journal_page_last 474 _publ_section_title ; The Structure of Norbergite _cod_database_code 1011009 ; _database_code_amcsd 0017920 _chemical_formula_sum 'O5 F Mg3 Si' _cell_length_a 4.7 _cell_length_b 10.2 _cell_length_c 8.72 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 418.037 _exptl_crystal_density_diffrn 3.178 _symmetry_space_group_name_H-M 'P b n m' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,y,1/2-z' '-x,-y,1/2+z' '1/2+x,1/2-y,1/2+z' '1/2-x,1/2+y,1/2-z' '1/2-x,1/2+y,z' '1/2+x,1/2-y,-z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy O1 0.25000 0.29200 0.08300 1.00000 O2 0.25000 0.04200 0.25000 1.00000 O3 -0.25000 0.20800 0.25000 1.00000 F1 -0.25000 -0.04200 0.08300 0.50000 O4 -0.25000 -0.04200 0.08300 0.50000 Mg1 0.00000 -0.36100 0.07800 1.00000 Mg2 0.01400 -0.11100 0.25000 1.00000 Si1 0.38900 -0.27800 0.25000 1.00000