data_global _chemical_name_mineral 'Fersmanite' loop_ _publ_author_name 'Sokolova E V' 'Hawthorne F C' 'Khomyakov A P' _journal_name_full 'The Canadian Mineralogist' _journal_volume 40 _journal_year 2002 _journal_page_first 1421 _journal_page_last 1428 _publ_section_title ; The crystal chemistry of fersmanite, Ca4(Na,Ca)4(Ti,Nb)4(Si2O7)2O8F3 ; _database_code_amcsd 5791 _chemical_formula_sum '(Ti2.39 Nb1.61) Ca5.49 Fe.03 Mn.03 Na2.37 Sr.08 Si4 O22 F3' _cell_length_a 10.183 _cell_length_b 10.183 _cell_length_c 20.396 _cell_angle_alpha 90.0 _cell_angle_beta 97.19 _cell_angle_gamma 90.0 _cell_volume 2098.302 _exptl_crystal_density_diffrn 3.388 _symmetry_space_group_name_H-M 'C 1 2/c 1' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2+y,z' 'x,-y,1/2+z' '1/2+x,1/2-y,1/2+z' '-x,y,1/2-z' '1/2-x,1/2+y,1/2-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 Ti-M1 0.10817 0.56293 0.18725 0.595 0.0149 Nb-M1 0.10817 0.56293 0.18725 0.405 0.0149 Ti-M2 0.14013 0.81125 0.31258 0.6 0.0145 Nb-M2 0.14013 0.81125 0.31258 0.4 0.0145 Ca-A1 0.33102 1.06505 0.06387 0.985 0.0192 Fe-A1 0.33102 1.06505 0.06387 0.007 0.0192 Mn-A1 0.33102 1.06505 0.06387 0.008 0.0192 Ca-A2 0.07673 0.8102 0.06675 0.985 0.0194 Fe-A2 0.07673 0.8102 0.06675 0.008 0.0194 Mn-A2 0.07673 0.8102 0.06675 0.007 0.0194 Na-A3 0.38457 0.55893 0.30528 0.58 0.0239 Ca-A3 0.38457 0.55893 0.30528 0.4 0.0239 Sr-A3 0.38457 0.55893 0.30528 0.02 0.0239 Na-A4 0.3575 0.81652 0.19449 0.605 0.023 Ca-A4 0.3575 0.81652 0.19449 0.375 0.023 Sr-A4 0.3575 0.81652 0.19449 0.02 0.023 Si1 -0.06952 0.70163 -0.08346 1.0 0.0141 Si2 0.15357 0.92428 -0.083 1.0 0.0145 O1 -0.2105 0.7588 -0.11832 1.0 0.0233 O2 -0.0213 0.5686 -0.11832 1.0 0.0231 O3 -0.0622 0.6891 -0.00553 1.0 0.0245 O4 0.0366 0.813 -0.10396 1.0 0.0287 O5 0.0878 1.0567 -0.11826 1.0 0.0238 O6 0.1849 0.9365 -0.00537 1.0 0.0283 O7 0.2773 0.8675 -0.11807 1.0 0.0242 O8 0.2586 0.9371 0.28388 1.0 0.019 O9 0.1915 0.6872 0.24989 1.0 0.0188 O10 0.0264 0.6869 0.35313 1.0 0.0166 O11 0.0 0.4963 0.25 1.0 0.0184 O12 0.0 0.8787 0.25 1.0 0.0204 F1 0.2213 0.9385 0.13101 1.0 0.0217 F2 0.5 0.6876 0.25 1.0 0.0266 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 Ti-M1 0.0141 0.0146 0.016 -3e-05 0.00143 -0.00018 Nb-M1 0.0141 0.0146 0.016 -3e-05 0.00143 -0.00018 Ti-M2 0.0133 0.0147 0.0152 -1e-05 0.00043 -0.0004 Nb-M2 0.0133 0.0147 0.0152 -1e-05 0.00043 -0.0004 Ca-A1 0.0199 0.021 0.0166 -0.0062 0.0011 0.0002 Fe-A1 0.0199 0.021 0.0166 -0.0062 0.0011 0.0002 Mn-A1 0.0199 0.021 0.0166 -0.0062 0.0011 0.0002 Ca-A2 0.0199 0.0207 0.0171 -0.0067 0.0009 -0.0003 Fe-A2 0.0199 0.0207 0.0171 -0.0067 0.0009 -0.0003 Mn-A2 0.0199 0.0207 0.0171 -0.0067 0.0009 -0.0003 Na-A3 0.024 0.0236 0.0243 -0.0025 0.0045 0.0021 Ca-A3 0.024 0.0236 0.0243 -0.0025 0.0045 0.0021 Sr-A3 0.024 0.0236 0.0243 -0.0025 0.0045 0.0021 Na-A4 0.0212 0.0232 0.0236 0.0027 -0.0006 0.0023 Ca-A4 0.0212 0.0232 0.0236 0.0027 -0.0006 0.0023 Sr-A4 0.0212 0.0232 0.0236 0.0027 -0.0006 0.0023 Si1 0.0132 0.0146 0.0139 0.0 -0.0008 -0.0022 Si2 0.0143 0.0148 0.0147 0.0003 0.0026 0.0022 O1 0.0195 0.0256 0.0235 0.0064 -0.002 -0.0042 O2 0.0251 0.0205 0.0223 0.0051 -0.0021 -0.0056 O3 0.0294 0.0277 0.0161 -0.0078 0.0013 -0.0004 O4 0.0275 0.0256 0.0327 -0.014 0.003 0.002 O5 0.0289 0.0209 0.023 0.0074 0.0092 0.0049 O6 0.0321 0.0364 0.016 -0.01 0.0009 -0.0003 O7 0.0222 0.029 0.0224 0.0059 0.0066 0.009 O8 0.0188 0.0187 0.0192 -0.003 0.0017 0.0011 O9 0.0198 0.0196 0.0169 -0.0022 0.0021 -0.0042 O10 0.0159 0.0147 0.0193 -0.0003 0.0022 -0.0014 O11 0.0185 0.0206 0.016 0.0 0.0026 0.0 O12 0.0215 0.0175 0.021 0.0 -0.0022 0.0 F1 0.0225 0.0238 0.0184 -0.0032 0.0018 -0.0008 F2 0.026 0.0233 0.03 0.0 0.0019 0.0