Octachlorosilasesquioxane, Cl~8~Si~8~O~12~
Törnroos, K. W.; Calzaferri, G.; Imhof, R.; Acta Crystallographica Section C 51 (1995) 1732–1735; doi:10.1107/S0108270195004410

data_2003855
_publ_section_title
;
 Octachlorosilasesquioxane, Cl~8~Si~8~O~12~
;
_journal_issue                   9
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              1732
_journal_page_last               1735
_journal_paper_doi               10.1107/S0108270195004410
_journal_volume                  51
_journal_year                    1995
_chemical_formula_sum            'Cl8 O12 Si8'
_chemical_formula_weight         700.32
_chemical_name_common            octachlorosilasesquioxane
_space_group_IT_number           148
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_Hall  '-R 3'
_symmetry_space_group_name_H-M   'R -3 :H'
_audit_creation_method           SHELXL
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            3
_cell_length_a                   12.353(2)
_cell_length_b                   12.353(2)
_cell_length_c                   12.931(2)
_cell_measurement_reflns_used    36
_cell_measurement_temperature    291(2)
_cell_measurement_theta_max      11.60
_cell_measurement_theta_min      4.95
_cell_volume                     1708.9(5)
_computing_cell_refinement       DIF4
_computing_data_collection       'DIF4 (Stoe & Cie, 1988a)'
_computing_data_reduction        'REDU4 (Stoe & Cie, 1988b)'
_computing_molecular_graphics    'SHELXTL-Plus (Sheldrick, 1991)'
_computing_structure_refinement  'SHELXL93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      291(2)
_diffrn_measurement_device       'Stoe AED-2'
_diffrn_measurement_method       \w/2\q
_diffrn_radiation_monochromator  Graphite
_diffrn_radiation_source         'Fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0000
_diffrn_reflns_av_sigmaI/netI    0.1872
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            1117
_diffrn_reflns_theta_max         30.00
_diffrn_reflns_theta_min         2.47
_diffrn_standards_decay_%        '<2.9 corrected by linear interpolation'
_diffrn_standards_interval_time  180
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    1.456
_exptl_absorpt_correction_T_max  0.9012
_exptl_absorpt_correction_T_min  0.8523
_exptl_absorpt_correction_type   analytical
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    2.041
_exptl_crystal_description       rhombic
_exptl_crystal_F_000             1032
_exptl_crystal_size_max          0.125
_exptl_crystal_size_mid          0.075
_exptl_crystal_size_min          0.075
_refine_diff_density_max         0.24
_refine_diff_density_min         -0.40
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_all   1.041
_refine_ls_goodness_of_fit_obs   1.184
_refine_ls_matrix_type           full
_refine_ls_number_parameters     43
_refine_ls_number_reflns         301
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.2354
_refine_ls_R_factor_obs          0.0459
_refine_ls_shift/esd_max         <0.001
_refine_ls_shift/esd_mean        <0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_scheme
;
calc w = 1/[\s^2^(F~o~^2^) + (0.0261P)^2^]
where P = (F~o~^2^ + 2F~c~^2^)/3
;
_refine_ls_wR_factor_all         0.1246
_refine_ls_wR_factor_obs         0.0700
_reflns_number_observed          301
_reflns_number_total             1117
_reflns_observed_criterion       >3sigma(I)
_cod_data_source_file            ab1255.cif
_cod_data_source_block           octachlorosilasesquioxane
_cod_original_cell_volume        1708.9(4)
_cod_original_sg_symbol_H-M      'R -3'
_cod_database_code               2003855