The polyoctahedral silsesquioxane (POSS) 1,3,5,7,9,11,13,15-octaphenylpentacyclo[9.5.1.1^3,9^.1^5,15^.1^7,13^]octasiloxane (octaphenyl-POSS)
Chinnam, Parameswara Rao; Gau, Michael R.; Schwab, Joseph; Zdilla, Michael J.; Wunder, Stephanie L.; Acta Crystallographica Section C 70 (2014) 971–974; doi:10.1107/S2053229614019834

data_2019670
_publ_section_title
;
 The polyoctahedral silsesquioxane (POSS)
 1,3,5,7,9,11,13,15-octaphenylpentacyclo[9.5.1.1^3,9^.1^5,15^.1^7,13^]octasiloxane
 (octaphenyl-POSS)
;
_journal_coeditor_code           FN3178
_journal_issue                   10
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              971
_journal_page_last               974
_journal_paper_doi               10.1107/S2053229614019834
_journal_volume                  70
_journal_year                    2014
_chemical_formula_iupac          'C48 H40 O12 Si8'
_chemical_formula_moiety         'C48 H40 O12 Si8'
_chemical_formula_sum            'C48 H40 O12 Si8'
_chemical_formula_weight         1033.52
_chemical_name_systematic
1,3,5,7,9,11,13,15-Octaphenylpentacyclo[9.5.1.1^3,9^.1^5,15^.1^7,13^]octasiloxane
_space_group_crystal_system      monoclinic
_space_group_IT_number           15
_space_group_name_Hall           '-C 2yc'
_space_group_name_H-M_alt        'C 1 2/c 1'
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2013
_cell_angle_alpha                90
_cell_angle_beta                 93.458(2)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   16.406(2)
_cell_length_b                   13.8849(17)
_cell_length_c                   21.570(3)
_cell_measurement_reflns_used    9926
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      27.96
_cell_measurement_theta_min      2.18
_cell_volume                     4904.6(11)
_computing_cell_refinement       'SAINT (Bruker, 2006)'
_computing_data_collection       'COSMO (Bruker, 2006)'
_computing_data_reduction        'SADABS (Bruker, 2006)'
_computing_molecular_graphics    'XP in SHELXL2013 (Sheldrick, 2013)'
_computing_publication_material  'APEX2 Report Generator (Bruker, 2006)'
_computing_structure_refinement  'SHELXL2013 (Sheldrick, 2013)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 8.333
_diffrn_measured_fraction_theta_full 0.975
_diffrn_measured_fraction_theta_max 0.965
_diffrn_measurement_device_type  'Bruker Kappa APEXII DUO'
_diffrn_measurement_method       \w
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0215
_diffrn_reflns_limit_h_max       21
_diffrn_reflns_limit_h_min       -21
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -28
_diffrn_reflns_number            16438
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.969
_diffrn_reflns_theta_min         1.892
_exptl_absorpt_coefficient_mu    0.281
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.6528
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Bruker, 2006)'
_exptl_crystal_colour            White
_exptl_crystal_density_diffrn    1.400
_exptl_crystal_description       Plate
_exptl_crystal_F_000             2144
_exptl_crystal_size_max          0.450
_exptl_crystal_size_mid          0.300
_exptl_crystal_size_min          0.070
_refine_diff_density_max         0.628
_refine_diff_density_min         -0.375
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.047
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     307
_refine_ls_number_reflns         5707
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.047
_refine_ls_R_factor_all          0.0388
_refine_ls_R_factor_gt           0.0351
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0485P)^2^+7.6053P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0919
_refine_ls_wR_factor_ref         0.0947
_reflns_number_gt                5201
_reflns_number_total             5707
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            fn3178sup1.cf
_cod_data_source_block           I
_cod_depositor_comments          'Adding full bibliography for 2019670.cif.'
_cod_original_cell_volume        4904.7(10)
_cod_database_code               2019670
_cod_database_fobs_code          2019670
_shelx_estimated_absorpt_t_min   0.884
_shelx_estimated_absorpt_t_max   0.981
_shelx_hkl_checksum              63993
_shelx_res_checksum              53975
_shelxl_version_number           2.013