data_global _chemical_name_mineral 'Normandite' loop_ _publ_author_name 'Perchiazzi N' 'McDonald A M' 'Gault R A' 'Johnsen O' 'Merlino S' _journal_name_full 'The Canadian Mineralogist' _journal_volume 38 _journal_year 2000 _journal_page_first 641 _journal_page_last 648 _publ_section_title ; The crystal structure of normandite and its crystal-chemical relationships with lavenite ; _database_code_amcsd 0005650 _chemical_compound_source 'Mont Saint-Hilaire, Quebec, Canada' _chemical_formula_sum '(Ti.876 Nb.124) Mn.784 Ca.936 Na1.28 Si2 O8 F' _cell_length_a 10.799 _cell_length_b 9.801 _cell_length_c 7.054 _cell_angle_alpha 90 _cell_angle_beta 108.075 _cell_angle_gamma 90 _cell_volume 709.758 _exptl_crystal_density_diffrn 3.431 _symmetry_space_group_name_H-M 'P 1 21/a 1' loop_ _space_group_symop_operation_xyz 'x,y,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 _atom_site_U_iso_or_equiv Ti 0.28342 0.10168 0.02100 0.87600 0.00540 Nb 0.28342 0.10168 0.02100 0.12400 0.00540 Mn 0.43676 0.36666 0.85877 0.78400 0.00926 Ca 0.43676 0.36666 0.85877 0.21600 0.00926 Ca 0.30008 0.10778 0.52449 0.72000 0.00955 Na 0.30008 0.10778 0.52449 0.28000 0.00955 Na 0.42430 0.37810 0.33720 1.00000 0.00890 Si1 0.62060 0.16450 0.21060 1.00000 0.00600 Si2 0.62090 0.16600 0.67040 1.00000 0.00600 O1 0.64310 0.16010 0.45160 1.00000 0.01470 O2 0.73950 0.26470 0.20140 1.00000 0.01020 O3 0.74610 0.25550 0.80020 1.00000 0.01030 O4 0.65270 0.01070 0.15890 1.00000 0.01100 O5 0.63340 0.00850 0.74310 1.00000 0.01140 O6 0.47650 0.22060 0.09670 1.00000 0.00950 O7 0.48430 0.23660 0.64850 1.00000 0.01190 O8 0.62620 0.47470 0.95710 1.00000 0.01270 F 0.38960 0.50540 0.59920 1.00000 0.01670