data_varana 1 _audit_creation_method SHELXL-97 _chemical_name_systematic ; ? ; _chemical_name_common ? _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'H8 Fe Mg5 O28 Si4' _chemical_formula_weight 745.82 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' 'Mg' 'Mg' 0.0486 0.0363 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'Fe' 'Fe' 0.3463 0.8444 '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' 'H' 'H' 0.0000 0.0000 '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' 'y, x, z' 'x-y, -y, z' '-x, -x+y, z' _cell_length_a 5.32590(10) _cell_length_b 5.32590(10) _cell_length_c 7.2726(3) _cell_angle_alpha 90.00 _cell_angle_beta 90.00 _cell_angle_gamma 120.00 _cell_volume 178.651(9) _cell_formula_units_Z 1 _cell_measurement_temperature 273(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 6.932 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 374 _exptl_absorpt_coefficient_mu 3.622 _exptl_absorpt_correction_type ? _exptl_absorpt_correction_T_min ? _exptl_absorpt_correction_T_max ? _exptl_absorpt_process_details ? _exptl_special_details ; ? ; _diffrn_ambient_temperature 273(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 1765 _diffrn_reflns_av_R_equivalents 0.0335 _diffrn_reflns_av_sigmaI/netI 0.0386 _diffrn_reflns_limit_h_min -8 _diffrn_reflns_limit_h_max 8 _diffrn_reflns_limit_k_min -6 _diffrn_reflns_limit_k_max 7 _diffrn_reflns_limit_l_min -11 _diffrn_reflns_limit_l_max 11 _diffrn_reflns_theta_min 4.42 _diffrn_reflns_theta_max 35.29 _reflns_number_total 567 _reflns_number_gt 547 _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^)+(0.0810P)^2^+0.0000P] 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 SHELXL _refine_ls_extinction_coef 0.00(4) _refine_ls_extinction_expression 'Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^' _refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881' _refine_ls_abs_structure_Flack 0.71(18) _refine_ls_number_reflns 567 _refine_ls_number_parameters 31 _refine_ls_number_restraints 1 _refine_ls_R_factor_all 0.0418 _refine_ls_R_factor_gt 0.0399 _refine_ls_wR_factor_ref 0.1020 _refine_ls_wR_factor_gt 0.1003 _refine_ls_goodness_of_fit_ref 1.044 _refine_ls_restrained_S_all 1.043 _refine_ls_shift/su_max 4.515 _refine_ls_shift/su_mean 0.760 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_symetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group Si Si 0.3333 0.6667 0.0758(2) 0.0072(4) Uani 1 3 d S . . Fe2 Fe 0.3325(2) 0.0000 0.4574(3) 0.0085(8) Uani 0.074(16) 2 d SP A 1 Mg2 Mg 0.3325(2) 0.0000 0.4574(3) 0.0085(8) Uani 0.926(16) 2 d SP . 2 O1 O 0.3333 0.6667 0.2957(6) 0.0069(7) Uani 1 3 d S . 2 O2 O 0.5066(6) 0.0000 -0.0063(5) 0.0133(7) Uani 1 2 d S . 2 O3 O 0.6657(5) 0.0000 0.5908(5) 0.0085(6) Uani 1 2 d S . 2 O4 O 0.0000 0.0000 0.3026(7) 0.0080(8) Uani 1 6 d S . 2 H3 H 0.8562 0.0000 0.5793 0.042(10) Uiso 1 2 d S B 2 H4 H 0.0000 0.0000 0.1590 0.042(10) Uiso 1 6 d S C 2 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 Si 0.0052(4) 0.0052(4) 0.0112(6) 0.000 0.000 0.0026(2) Fe2 0.0053(9) 0.0056(10) 0.0147(11) 0.000 0.0000(3) 0.0028(5) Mg2 0.0053(9) 0.0056(10) 0.0147(11) 0.000 0.0000(3) 0.0028(5) O1 0.0062(10) 0.0062(10) 0.0082(14) 0.000 0.000 0.0031(5) O2 0.0154(14) 0.0085(15) 0.0137(14) 0.000 0.0002(9) 0.0043(7) O3 0.0090(10) 0.0094(13) 0.0072(12) 0.000 0.0001(6) 0.0047(6) O4 0.0073(13) 0.0073(13) 0.0093(17) 0.000 0.000 0.0036(6) _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 Si O1 1.600(5) . ? Si O2 1.6496(14) 2 ? Si O2 1.6496(14) 1_565 ? Si O2 1.6496(14) 3_665 ? O1 Mg2 2.131(3) 1_565 ? O1 Mg2 2.131(3) 2 ? O1 Mg2 2.131(3) 3_665 ? O2 Si 1.6496(14) 4 ? O2 Si 1.6496(14) 1_545 ? O3 Mg2 2.024(2) 3_655 ? O3 Mg2 2.024(2) 2_655 ? O3 H3 1.018(3) . ? O4 Mg2 2.098(3) 2 ? O4 Mg2 2.098(3) 3 ? O4 H4 1.045(5) . ? 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 O1 Si O2 111.21(12) . 2 ? O1 Si O2 111.21(12) . 1_565 ? O2 Si O2 107.68(13) 2 1_565 ? O1 Si O2 111.21(12) . 3_665 ? O2 Si O2 107.68(13) 2 3_665 ? O2 Si O2 107.68(13) 1_565 3_665 ? Si O1 Mg2 123.47(10) . 1_565 ? Si O1 Mg2 123.47(10) . 2 ? Mg2 O1 Mg2 92.50(14) 1_565 2 ? Si O1 Mg2 123.47(10) . 3_665 ? Mg2 O1 Mg2 92.50(14) 1_565 3_665 ? Mg2 O1 Mg2 92.50(14) 2 3_665 ? Si O2 Si 137.5(2) 4 1_545 ? Mg2 O3 Mg2 98.57(16) 3_655 2_655 ? Mg2 O3 H3 61.30(11) 3_655 . ? Mg2 O3 H3 61.30(11) 2_655 . ? Mg2 O4 Mg2 93.94(18) 2 3 ? Mg2 O4 H4 122.43(13) 2 . ? Mg2 O4 H4 122.43(13) 3 . ? _diffrn_measured_fraction_theta_max 0.962 _diffrn_reflns_theta_full 35.29 _diffrn_measured_fraction_theta_full 0.962 _refine_diff_density_max 3.842 _refine_diff_density_min -0.644 _refine_diff_density_rms 0.179