data_global _chemical_name_mineral 'Fluorbritholite-(Ce)' loop_ _publ_author_name 'Oberti R' 'Ottolini L' 'Della Ventura G' 'Parodi G C' _journal_name_full 'American Mineralogist' _journal_volume 86 _journal_year 2001 _journal_page_first 1066 _journal_page_last 1075 _publ_section_title ; On the symmetry and crystal chemistry of britholite: New structural and microanalytical data Sample: LOS from Rouma Island, Guinea ; _database_code_amcsd 0002670 _chemical_formula_sum 'Si2.55 P.39 Na.5 Ca1.03 La1.47 Ce1.67 Pr.1 Nd.23 O12.12 F.88 H.12' _cell_length_a 9.682 _cell_length_b 9.682 _cell_length_c 7.066 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _cell_volume 573.633 _exptl_crystal_density_diffrn 4.821 _symmetry_space_group_name_H-M 'P 63' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x-y,x,1/2+z' '-y,x-y,z' '-x,-y,1/2+z' '-x+y,-x,z' 'y,-x+y,1/2+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 Si1 0.40070 0.37280 0.25640 0.85000 0.00861 P1 0.40070 0.37280 0.25640 0.13000 0.00861 Na1 0.33333 0.66667 -0.00390 0.25000 0.01077 Ca1 0.33333 0.66667 -0.00390 0.17000 0.01077 La1 0.33333 0.66667 -0.00390 0.24000 0.01077 Ce1 0.33333 0.66667 -0.00390 0.28000 0.01077 Pr1 0.33333 0.66667 -0.00390 0.02000 0.01077 Nd1 0.33333 0.66667 -0.00390 0.04000 0.01077 Na1a 0.66667 0.33333 0.00600 0.25000 0.01039 Ca1a 0.66667 0.33333 0.00600 0.17000 0.01039 La1a 0.66667 0.33333 0.00600 0.24000 0.01039 Ce1a 0.66667 0.33333 0.00600 0.28000 0.01039 Pr1a 0.66667 0.33333 0.00600 0.02000 0.01039 Nd1a 0.66667 0.33333 0.00600 0.04000 0.01039 Ca2 0.23640 -0.01330 0.25000 0.23000 0.01102 La2 0.23640 -0.01330 0.25000 0.33000 0.01102 Ce2 0.23640 -0.01330 0.25000 0.37000 0.01102 Pr2 0.23640 -0.01330 0.25000 0.02000 0.01102 Nd2 0.23640 -0.01330 0.25000 0.05000 0.01102 O1 0.32460 0.48680 0.25890 1.00000 0.01836 O2 0.59290 0.46930 0.25390 1.00000 0.02254 O3 0.31200 0.24450 0.41740 1.00000 0.02672 O3a 0.36500 0.26500 0.06330 1.00000 0.01710 O-H4 0.00000 0.00000 0.17710 0.12000 0.06814 F4 0.00000 0.00000 0.23590 0.88000 0.06814