Optical anomaly in artificial cubic hieratite, K~2~[SiF~6~]
Göbel, Ole F.; ten Elshof, Johan E.; Kaminsky, Werner; Hannss, Matthias; Acta Crystallographica Section B 71 (2015) 328–333; doi:10.1107/S2052520615007507

data_2106022
_publ_section_title
;
 Optical anomaly in artificial cubic hieratite, K~2~[SiF~6~]
;
_journal_coeditor_code           XK5019
_journal_issue                   3
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              328
_journal_page_last               333
_journal_paper_doi               10.1107/S2052520615007507
_journal_volume                  71
_journal_year                    2015
_chemical_formula_sum            'F6 K2 Si'
_chemical_formula_weight         220.29
_chemical_name_systematic
;
 ?
;
_space_group_IT_number           225
_symmetry_cell_setting           cubic
_symmetry_space_group_name_Hall  '-F 4 2 3'
_symmetry_space_group_name_H-M   'F m -3 m'
_atom_sites_solution_hydrogens   notdet
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.1345(8)
_cell_length_b                   8.1345(8)
_cell_length_c                   8.1345(8)
_cell_measurement_reflns_used    2659
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      39.95
_cell_measurement_theta_min      5.01
_cell_volume                     538.26(9)
_computing_cell_refinement       'SAINT V7.68A (Bruker, 2010)'
_computing_data_collection       'Apex2 (Bruker, 2010)'
_computing_data_reduction
'SAINT V7.68A (Bruker, 2010), SADABS-2008/1 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 0.959
_diffrn_measured_fraction_theta_max 0.959
_diffrn_measurement_device_type  'Bruker Kappa ApexII area detector'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  Triumph
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0139
_diffrn_reflns_av_sigmaI/netI    0.0039
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            3622
_diffrn_reflns_theta_full        40.28
_diffrn_reflns_theta_max         40.28
_diffrn_reflns_theta_min         5.01
_exptl_absorpt_coefficient_mu    2.021
_exptl_absorpt_correction_T_max  0.7479
_exptl_absorpt_correction_T_min  0.7057
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS-2008/1 (Sheldrick, 2008)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    2.718
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       cube
_exptl_crystal_F_000             424
_exptl_crystal_size_max          0.26
_exptl_crystal_size_mid          0.26
_exptl_crystal_size_min          0.26
_refine_diff_density_max         0.279
_refine_diff_density_min         -0.299
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.120
_refine_ls_hydrogen_treatment    undef
_refine_ls_matrix_type           full
_refine_ls_number_parameters     6
_refine_ls_number_reflns         116
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.120
_refine_ls_R_factor_all          0.0162
_refine_ls_R_factor_gt           0.0159
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0189P)^2^+0.3956P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0425
_refine_ls_wR_factor_ref         0.0425
_reflns_number_gt                113
_reflns_number_total             116
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            xk5019sup1.cf
_cod_data_source_block           I
_cod_database_code               2106022
_cod_database_fobs_code 2106022