data_LAURENTIANITE _audit_creation_method SHELXL-97 _chemical_name_systematic ; ? ; _chemical_name_common ? _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'Na3 Nb3 O26 Si4' _chemical_formula_weight 876.06 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source 'O' 'O' 0.0106 0.0060 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'Na' 'Na' 0.0362 0.0249 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'Si' 'Si' 0.0817 0.0704 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'Nb' 'Nb' -2.0727 0.6215 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting ? _symmetry_space_group_name_H-M ? loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-y, x-y, z' '-x+y, -x, z' _cell_length_a 9.9370(14) _cell_length_b 9.9370(14) _cell_length_c 7.0040(14) _cell_angle_alpha 90.00 _cell_angle_beta 90.00 _cell_angle_gamma 120.00 _cell_volume 598.95(17) _cell_formula_units_Z 1 _cell_measurement_temperature 293(2) _cell_measurement_reflns_used ? _cell_measurement_theta_min ? _cell_measurement_theta_max ? _exptl_crystal_description ? _exptl_crystal_colour ? _exptl_crystal_size_max ? _exptl_crystal_size_mid ? _exptl_crystal_size_min ? _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 2.429 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 420 _exptl_absorpt_coefficient_mu 1.774 _exptl_absorpt_correction_type ? _exptl_absorpt_correction_T_min ? _exptl_absorpt_correction_T_max ? _exptl_absorpt_process_details ? _exptl_special_details ; ? ; _diffrn_ambient_temperature 293(2) _diffrn_radiation_wavelength 0.71073 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device_type ? _diffrn_measurement_method ? _diffrn_detector_area_resol_mean ? _diffrn_standards_number ? _diffrn_standards_interval_count ? _diffrn_standards_interval_time ? _diffrn_standards_decay_% ? _diffrn_reflns_number 6990 _diffrn_reflns_av_R_equivalents 0.0232 _diffrn_reflns_av_sigmaI/netI 0.0222 _diffrn_reflns_limit_h_min -14 _diffrn_reflns_limit_h_max 14 _diffrn_reflns_limit_k_min -14 _diffrn_reflns_limit_k_max 14 _diffrn_reflns_limit_l_min -9 _diffrn_reflns_limit_l_max 9 _diffrn_reflns_theta_min 2.37 _diffrn_reflns_theta_max 30.08 _reflns_number_total 2346 _reflns_number_gt 2270 _reflns_threshold_expression >2sigma(I) _computing_data_collection ? _computing_cell_refinement ? _computing_data_reduction ? _computing_structure_solution 'SHELXS-97 (Sheldrick, 1990)' _computing_structure_refinement 'SHELXL-97 (Sheldrick, 1997)' _computing_molecular_graphics ? _computing_publication_material ? _refine_special_details ; Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2sigma(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.0497P)^2^+0.1345P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment mixed _refine_ls_extinction_method none _refine_ls_extinction_coef ? _refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881' _refine_ls_abs_structure_Flack 0.32(8) _refine_ls_number_reflns 2346 _refine_ls_number_parameters 122 _refine_ls_number_restraints 1 _refine_ls_R_factor_all 0.0292 _refine_ls_R_factor_gt 0.0278 _refine_ls_wR_factor_ref 0.0794 _refine_ls_wR_factor_gt 0.0785 _refine_ls_goodness_of_fit_ref 1.181 _refine_ls_restrained_S_all 1.181 _refine_ls_shift/su_max 0.005 _refine_ls_shift/su_mean 0.001 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symmetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group Na1 Na 0.3304(6) 0.1643(4) 1.2430(9) 0.0236(5) Uani 0.926(7) 1 d P . . Nb1 Nb 0.33262(12) 0.12933(12) 0.74827(18) 0.00968(15) Uani 0.55 1 d P . . Nb2 Nb 0.33217(18) 0.20147(17) 0.7389(3) 0.0137(3) Uani 0.45 1 d P . . Si1 Si 0.6667 0.3333 1.0157(4) 0.0086(5) Uani 1 3 d S . . Si2 Si 0.6667 0.3333 1.4783(3) 0.0089(6) Uani 1 3 d S . . Si3 Si 0.0000 0.0000 1.0161(3) 0.0100(6) Uani 1 3 d S . . Si4 Si 0.0000 0.0000 1.4780(4) 0.0103(6) Uani 1 3 d S . . O1 O 0.6667 0.3333 1.2376(12) 0.0182(17) Uani 1 3 d S . . O2 O 0.1777(6) 0.1020(6) 0.9435(6) 0.0197(10) Uani 1 1 d . . . O3 O 0.4853(8) 0.2547(7) 0.9533(6) 0.0219(10) Uani 1 1 d . . . O4 O 0.0000 0.0000 1.2380(12) 0.0205(18) Uani 1 3 d S . . O5 O 0.1742(7) 0.0747(6) 0.5527(6) 0.0190(9) Uani 1 1 d . . . O6 O 0.4893(8) 0.2318(6) 0.5435(7) 0.0236(11) Uani 1 1 d . . . O7 O 0.3328(6) 0.3796(5) 0.7136(7) 0.0192(9) Uani 1 1 d . . . O8 O 0.3321(7) -0.0485(6) 0.7813(7) 0.0274(12) Uani 1 1 d . . . OW9 O 0.3320(7) 0.3999(6) 1.3090(8) 0.0361(13) Uani 1 1 d . . . OW10 O 0.0747(8) 0.4064(7) 1.1924(8) 0.0464(16) Uani 1 1 d . . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 Na1 0.0262(7) 0.0311(11) 0.0122(7) -0.0054(9) -0.0002(4) 0.0133(9) Nb1 0.0108(3) 0.0156(4) 0.0012(3) 0.0019(3) -0.0001(2) 0.0055(4) Nb2 0.0116(5) 0.0162(6) 0.0120(6) -0.0002(4) -0.0003(3) 0.0060(5) Si1 0.0115(9) 0.0115(9) 0.0030(11) 0.000 0.000 0.0057(4) Si2 0.0123(9) 0.0123(9) 0.0022(13) 0.000 0.000 0.0062(5) Si3 0.0126(9) 0.0126(9) 0.0048(13) 0.000 0.000 0.0063(4) Si4 0.0135(9) 0.0135(9) 0.0039(11) 0.000 0.000 0.0068(5) O1 0.027(3) 0.027(3) 0.000(3) 0.000 0.000 0.0136(13) O2 0.009(2) 0.032(3) 0.0085(17) 0.0042(15) 0.0051(17) 0.0027(18) O3 0.019(2) 0.038(3) 0.0090(15) -0.0084(16) -0.0059(14) 0.0137(19) O4 0.031(3) 0.031(3) 0.000(3) 0.000 0.000 0.0153(14) O5 0.0098(18) 0.029(2) 0.0125(16) 0.0019(15) -0.0028(13) 0.0051(17) O6 0.024(3) 0.024(3) 0.020(2) 0.0012(16) 0.007(2) 0.009(2) O7 0.0225(19) 0.021(2) 0.018(2) 0.0038(15) 0.0006(19) 0.0138(18) O8 0.028(2) 0.024(3) 0.026(3) -0.0034(17) 0.000(2) 0.010(2) OW9 0.047(3) 0.032(2) 0.030(2) 0.0171(18) 0.004(2) 0.020(2) OW10 0.071(4) 0.052(4) 0.023(2) 0.000(2) 0.003(2) 0.037(3) _geom_special_details ; All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag Na1 OW9 2.378(7) . ? Na1 OW10 2.408(8) 3 ? Na1 O3 2.431(8) . ? Na1 O2 2.479(8) . ? Na1 O6 2.513(9) 1_556 ? Na1 O5 2.554(8) 1_556 ? Na1 O4 2.844(5) . ? Na1 O1 2.894(5) . ? Na1 Si3 3.258(6) . ? Na1 Si4 3.285(6) . ? Na1 Si1 3.303(6) . ? Na1 Si2 3.330(6) . ? Nb1 Nb2 0.7221(7) . ? Nb1 O8 1.780(6) . ? Nb1 O5 1.948(5) . ? Nb1 O2 1.973(5) . ? Nb1 O6 1.983(6) . ? Nb1 O3 2.006(6) . ? Nb1 O7 2.498(5) . ? Nb1 Na1 3.557(6) 1_554 ? Nb2 O7 1.776(5) . ? Nb2 O5 1.943(6) . ? Nb2 O2 1.967(5) . ? Nb2 O6 1.983(6) . ? Nb2 O3 2.011(6) . ? Nb2 O8 2.502(6) . ? Nb2 Na1 3.492(6) 1_554 ? Si1 O1 1.554(9) . ? Si1 O3 1.625(7) 2_655 ? Si1 O3 1.625(7) 3_665 ? Si1 O3 1.625(7) . ? Si1 Na1 3.303(6) 2_655 ? Si1 Na1 3.303(6) 3_665 ? Si2 O6 1.598(7) 2_656 ? Si2 O6 1.598(7) 3_666 ? Si2 O6 1.598(7) 1_556 ? Si2 O1 1.686(9) . ? Si2 Na1 3.330(6) 2_655 ? Si2 Na1 3.330(6) 3_665 ? Si3 O4 1.555(9) . ? Si3 O2 1.617(5) 2 ? Si3 O2 1.617(5) . ? Si3 O2 1.617(5) 3 ? Si3 Na1 3.258(6) 3 ? Si3 Na1 3.258(6) 2 ? Si4 O5 1.593(6) 1_556 ? Si4 O5 1.593(6) 3_556 ? Si4 O5 1.593(6) 2_556 ? Si4 O4 1.681(9) . ? Si4 Na1 3.285(6) 3 ? Si4 Na1 3.285(6) 2 ? O1 Na1 2.894(5) 2_655 ? O1 Na1 2.894(5) 3_665 ? O4 Na1 2.844(5) 3 ? O4 Na1 2.844(5) 2 ? O5 Si4 1.593(6) 1_554 ? O5 Na1 2.554(8) 1_554 ? O6 Si2 1.598(7) 1_554 ? O6 Na1 2.513(9) 1_554 ? OW10 Na1 2.408(8) 2 ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag OW9 Na1 OW10 177.2(3) . 3 ? OW9 Na1 O3 96.1(2) . . ? OW10 Na1 O3 85.8(2) 3 . ? OW9 Na1 O2 96.5(2) . . ? OW10 Na1 O2 86.2(2) 3 . ? O3 Na1 O2 65.3(2) . . ? OW9 Na1 O6 83.1(2) . 1_556 ? OW10 Na1 O6 94.2(2) 3 1_556 ? O3 Na1 O6 113.8(3) . 1_556 ? O2 Na1 O6 178.9(3) . 1_556 ? OW9 Na1 O5 83.2(2) . 1_556 ? OW10 Na1 O5 94.8(2) 3 1_556 ? O3 Na1 O5 178.4(4) . 1_556 ? O2 Na1 O5 116.2(3) . 1_556 ? O6 Na1 O5 64.7(2) 1_556 1_556 ? OW9 Na1 O4 90.3(2) . . ? OW10 Na1 O4 90.3(2) 3 . ? O3 Na1 O4 122.5(3) . . ? O2 Na1 O4 57.3(3) . . ? O6 Na1 O4 123.7(3) 1_556 . ? O5 Na1 O4 59.0(3) 1_556 . ? OW9 Na1 O1 89.6(2) . . ? OW10 Na1 O1 89.8(2) 3 . ? O3 Na1 O1 56.0(3) . . ? O2 Na1 O1 121.2(3) . . ? O6 Na1 O1 57.8(3) 1_556 . ? O5 Na1 O1 122.5(3) 1_556 . ? O4 Na1 O1 178.5(4) . . ? OW9 Na1 Si3 95.6(2) . . ? OW10 Na1 Si3 86.3(2) 3 . ? O3 Na1 Si3 94.1(2) . . ? O2 Na1 Si3 28.88(14) . . ? O6 Na1 Si3 152.1(3) 1_556 . ? O5 Na1 Si3 87.43(19) 1_556 . ? O4 Na1 Si3 28.50(19) . . ? O1 Na1 Si3 150.0(3) . . ? OW9 Na1 Si4 84.56(18) . . ? OW10 Na1 Si4 94.6(2) 3 . ? O3 Na1 Si4 153.2(3) . . ? O2 Na1 Si4 87.99(19) . . ? O6 Na1 Si4 93.0(2) 1_556 . ? O5 Na1 Si4 28.27(15) 1_556 . ? O4 Na1 Si4 30.76(19) . . ? O1 Na1 Si4 150.7(3) . . ? Si3 Na1 Si4 59.27(10) . . ? OW9 Na1 Si1 94.93(19) . . ? OW10 Na1 Si1 85.85(19) 3 . ? O3 Na1 Si1 28.02(17) . . ? O2 Na1 Si1 93.2(2) . . ? O6 Na1 Si1 85.8(2) 1_556 . ? O5 Na1 Si1 150.5(3) 1_556 . ? O4 Na1 Si1 150.5(3) . . ? O1 Na1 Si1 28.07(18) . . ? Si3 Na1 Si1 122.0(2) . . ? Si4 Na1 Si1 178.7(2) . . ? OW9 Na1 Si2 84.0(2) . . ? OW10 Na1 Si2 94.1(2) 3 . ? O3 Na1 Si2 86.4(2) . . ? O2 Na1 Si2 151.5(2) . . ? O6 Na1 Si2 27.46(16) 1_556 . ? O5 Na1 Si2 92.1(2) 1_556 . ? O4 Na1 Si2 151.0(3) . . ? O1 Na1 Si2 30.41(19) . . ? Si3 Na1 Si2 179.45(19) . . ? Si4 Na1 Si2 120.3(2) . . ? Si1 Na1 Si2 58.48(9) . . ? Nb2 Nb1 O8 177.7(2) . . ? Nb2 Nb1 O5 78.9(2) . . ? O8 Nb1 O5 102.4(3) . . ? Nb2 Nb1 O2 78.9(2) . . ? O8 Nb1 O2 99.1(2) . . ? O5 Nb1 O2 89.0(2) . . ? Nb2 Nb1 O6 79.5(2) . . ? O8 Nb1 O6 102.4(2) . . ? O5 Nb1 O6 87.3(2) . . ? O2 Nb1 O6 158.4(2) . . ? Nb2 Nb1 O3 80.0(2) . . ? O8 Nb1 O3 98.6(2) . . ? O5 Nb1 O3 158.6(2) . . ? O2 Nb1 O3 83.4(2) . . ? O6 Nb1 O3 92.5(2) . . ? Nb2 Nb1 O7 0.5(2) . . ? O8 Nb1 O7 178.1(3) . . ? O5 Nb1 O7 78.88(17) . . ? O2 Nb1 O7 79.44(19) . . ? O6 Nb1 O7 78.98(18) . . ? O3 Nb1 O7 80.07(19) . . ? Nb2 Nb1 Na1 89.29(16) . . ? O8 Nb1 Na1 88.45(18) . . ? O5 Nb1 Na1 133.06(16) . . ? O2 Nb1 Na1 44.04(17) . . ? O6 Nb1 Na1 135.28(18) . . ? O3 Nb1 Na1 42.8(2) . . ? O7 Nb1 Na1 89.67(11) . . ? Nb2 Nb1 Na1 79.01(19) . 1_554 ? O8 Nb1 Na1 103.25(17) . 1_554 ? O5 Nb1 Na1 44.28(18) . 1_554 ? O2 Nb1 Na1 131.33(15) . 1_554 ? O6 Nb1 Na1 43.3(2) . 1_554 ? O3 Nb1 Na1 133.71(17) . 1_554 ? O7 Nb1 Na1 78.64(12) . 1_554 ? Na1 Nb1 Na1 168.29(11) . 1_554 ? Nb1 Nb2 O7 179.3(3) . . ? Nb1 Nb2 O5 79.7(2) . . ? O7 Nb2 O5 100.3(2) . . ? Nb1 Nb2 O2 79.9(2) . . ? O7 Nb2 O2 100.8(2) . . ? O5 Nb2 O2 89.4(2) . . ? Nb1 Nb2 O6 79.53(19) . . ? O7 Nb2 O6 99.8(2) . . ? O5 Nb2 O6 87.4(3) . . ? O2 Nb2 O6 159.5(2) . . ? Nb1 Nb2 O3 79.3(2) . . ? O7 Nb2 O3 100.8(2) . . ? O5 Nb2 O3 158.7(2) . . ? O2 Nb2 O3 83.4(2) . . ? O6 Nb2 O3 92.3(3) . . ? Nb1 Nb2 O8 1.64(15) . . ? O7 Nb2 O8 178.9(3) . . ? O5 Nb2 O8 80.6(2) . . ? O2 Nb2 O8 78.56(19) . . ? O6 Nb2 O8 80.9(2) . . ? O3 Nb2 O8 78.3(2) . . ? Nb1 Nb2 Na1 89.28(19) . 1_554 ? O7 Nb2 Na1 90.20(18) . 1_554 ? O5 Nb2 Na1 45.89(18) . 1_554 ? O2 Nb2 Na1 135.24(17) . 1_554 ? O6 Nb2 Na1 44.9(2) . 1_554 ? O3 Nb2 Na1 137.18(18) . 1_554 ? O8 Nb2 Na1 90.89(15) . 1_554 ? Nb1 Nb2 Na1 78.97(16) . . ? O7 Nb2 Na1 101.56(19) . . ? O5 Nb2 Na1 129.80(17) . . ? O2 Nb2 Na1 42.35(18) . . ? O6 Nb2 Na1 131.69(18) . . ? O3 Nb2 Na1 41.3(2) . . ? O8 Nb2 Na1 77.36(14) . . ? Na1 Nb2 Na1 168.24(11) 1_554 . ? O1 Si1 O3 105.60(19) . 2_655 ? O1 Si1 O3 105.60(19) . 3_665 ? O3 Si1 O3 113.05(16) 2_655 3_665 ? O1 Si1 O3 105.60(19) . . ? O3 Si1 O3 113.05(16) 2_655 . ? O3 Si1 O3 113.05(16) 3_665 . ? O1 Si1 Na1 61.18(11) . 2_655 ? O3 Si1 Na1 44.64(19) 2_655 2_655 ? O3 Si1 Na1 119.49(19) 3_665 2_655 ? O3 Si1 Na1 127.47(19) . 2_655 ? O1 Si1 Na1 61.18(12) . 3_665 ? O3 Si1 Na1 127.47(19) 2_655 3_665 ? O3 Si1 Na1 44.64(19) 3_665 3_665 ? O3 Si1 Na1 119.49(19) . 3_665 ? Na1 Si1 Na1 98.71(15) 2_655 3_665 ? O1 Si1 Na1 61.18(12) . . ? O3 Si1 Na1 119.49(19) 2_655 . ? O3 Si1 Na1 127.47(19) 3_665 . ? O3 Si1 Na1 44.64(19) . . ? Na1 Si1 Na1 98.71(15) 2_655 . ? Na1 Si1 Na1 98.71(15) 3_665 . ? O6 Si2 O6 112.19(19) 2_656 3_666 ? O6 Si2 O6 112.19(19) 2_656 1_556 ? O6 Si2 O6 112.19(19) 3_666 1_556 ? O6 Si2 O1 106.6(2) 2_656 . ? O6 Si2 O1 106.6(2) 3_666 . ? O6 Si2 O1 106.6(2) 1_556 . ? O6 Si2 Na1 46.5(2) 2_656 2_655 ? O6 Si2 Na1 127.90(18) 3_666 2_655 ? O6 Si2 Na1 119.90(17) 1_556 2_655 ? O1 Si2 Na1 60.34(11) . 2_655 ? O6 Si2 Na1 127.90(18) 2_656 . ? O6 Si2 Na1 119.90(17) 3_666 . ? O6 Si2 Na1 46.5(2) 1_556 . ? O1 Si2 Na1 60.34(11) . . ? Na1 Si2 Na1 97.62(14) 2_655 . ? O6 Si2 Na1 119.90(17) 2_656 3_665 ? O6 Si2 Na1 46.5(2) 3_666 3_665 ? O6 Si2 Na1 127.90(18) 1_556 3_665 ? O1 Si2 Na1 60.34(11) . 3_665 ? Na1 Si2 Na1 97.62(14) 2_655 3_665 ? Na1 Si2 Na1 97.62(14) . 3_665 ? O4 Si3 O2 108.31(17) . 2 ? O4 Si3 O2 108.31(17) . . ? O2 Si3 O2 110.60(16) 2 . ? O4 Si3 O2 108.31(17) . 3 ? O2 Si3 O2 110.60(16) 2 3 ? O2 Si3 O2 110.60(16) . 3 ? O4 Si3 Na1 60.79(11) . . ? O2 Si3 Na1 128.99(18) 2 . ? O2 Si3 Na1 47.77(18) . . ? O2 Si3 Na1 120.20(18) 3 . ? O4 Si3 Na1 60.79(11) . 3 ? O2 Si3 Na1 120.20(18) 2 3 ? O2 Si3 Na1 128.99(18) . 3 ? O2 Si3 Na1 47.77(18) 3 3 ? Na1 Si3 Na1 98.21(14) . 3 ? O4 Si3 Na1 60.79(11) . 2 ? O2 Si3 Na1 47.77(18) 2 2 ? O2 Si3 Na1 120.20(18) . 2 ? O2 Si3 Na1 128.99(18) 3 2 ? Na1 Si3 Na1 98.21(14) . 2 ? Na1 Si3 Na1 98.21(14) 3 2 ? O5 Si4 O5 109.76(19) 1_556 3_556 ? O5 Si4 O5 109.76(19) 1_556 2_556 ? O5 Si4 O5 109.76(19) 3_556 2_556 ? O5 Si4 O4 109.18(19) 1_556 . ? O5 Si4 O4 109.18(19) 3_556 . ? O5 Si4 O4 109.18(19) 2_556 . ? O5 Si4 Na1 121.09(18) 1_556 3 ? O5 Si4 Na1 49.4(2) 3_556 3 ? O5 Si4 Na1 128.88(17) 2_556 3 ? O4 Si4 Na1 59.94(12) . 3 ? O5 Si4 Na1 49.4(2) 1_556 . ? O5 Si4 Na1 128.88(16) 3_556 . ? O5 Si4 Na1 121.09(18) 2_556 . ? O4 Si4 Na1 59.94(12) . . ? Na1 Si4 Na1 97.10(15) 3 . ? O5 Si4 Na1 128.88(17) 1_556 2 ? O5 Si4 Na1 121.09(18) 3_556 2 ? O5 Si4 Na1 49.4(2) 2_556 2 ? O4 Si4 Na1 59.94(12) . 2 ? Na1 Si4 Na1 97.10(15) 3 2 ? Na1 Si4 Na1 97.10(15) . 2 ? Si1 O1 Si2 180.000(1) . . ? Si1 O1 Na1 90.8(2) . 2_655 ? Si2 O1 Na1 89.2(2) . 2_655 ? Si1 O1 Na1 90.8(2) . 3_665 ? Si2 O1 Na1 89.2(2) . 3_665 ? Na1 O1 Na1 119.983(13) 2_655 3_665 ? Si1 O1 Na1 90.8(2) . . ? Si2 O1 Na1 89.2(2) . . ? Na1 O1 Na1 119.983(13) 2_655 . ? Na1 O1 Na1 119.983(11) 3_665 . ? Si3 O2 Nb2 151.3(3) . . ? Si3 O2 Nb1 146.8(3) . . ? Nb2 O2 Nb1 21.12(5) . . ? Si3 O2 Na1 103.4(2) . . ? Nb2 O2 Na1 105.3(3) . . ? Nb1 O2 Na1 102.4(3) . . ? Si1 O3 Nb1 143.5(3) . . ? Si1 O3 Nb2 147.0(3) . . ? Nb1 O3 Nb2 20.71(6) . . ? Si1 O3 Na1 107.3(3) . . ? Nb1 O3 Na1 103.0(3) . . ? Nb2 O3 Na1 105.7(3) . . ? Si3 O4 Si4 180.000(1) . . ? Si3 O4 Na1 90.7(2) . . ? Si4 O4 Na1 89.3(2) . . ? Si3 O4 Na1 90.7(2) . 3 ? Si4 O4 Na1 89.3(2) . 3 ? Na1 O4 Na1 119.985(10) . 3 ? Si3 O4 Na1 90.7(2) . 2 ? Si4 O4 Na1 89.3(2) . 2 ? Na1 O4 Na1 119.985(12) . 2 ? Na1 O4 Na1 119.985(11) 3 2 ? Si4 O5 Nb2 149.4(3) 1_554 . ? Si4 O5 Nb1 154.1(3) 1_554 . ? Nb2 O5 Nb1 21.39(6) . . ? Si4 O5 Na1 102.3(2) 1_554 1_554 ? Nb2 O5 Na1 101.0(3) . 1_554 ? Nb1 O5 Na1 103.6(3) . 1_554 ? Si2 O6 Nb2 146.0(4) 1_554 . ? Si2 O6 Nb1 150.0(4) 1_554 . ? Nb2 O6 Nb1 20.98(7) . . ? Si2 O6 Na1 106.1(3) 1_554 1_554 ? Nb2 O6 Na1 101.3(3) . 1_554 ? Nb1 O6 Na1 104.0(3) . 1_554 ? Nb2 O7 Nb1 0.21(8) . . ? Nb1 O8 Nb2 0.66(6) . . ? _diffrn_measured_fraction_theta_max 0.998 _diffrn_reflns_theta_full 30.08 _diffrn_measured_fraction_theta_full 0.998 _refine_diff_density_max 0.492 _refine_diff_density_min -1.143 _refine_diff_density_rms 0.106