Disorder and pseudo-symmetry in octakis(trivinylsilyl)octasilicate
Slebodnick, Carla; Angel, Ross J.; Hanson, Brian E.; Agaskar, Pradyot A.; Soler, Tatiana; Falvello, Larry R.; Acta Crystallographica Section B 64 (2008) 330–337; doi:10.1107/S0108768108010227

data_2104157
_publ_section_title
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 Disorder and pseudo-symmetry in octakis(trivinylsilyl)octasilicate
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_journal_coeditor_code           WS5065
_journal_issue                   3
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              330
_journal_page_last               337
_journal_paper_doi               10.1107/S0108768108010227
_journal_volume                  64
_journal_year                    2008
_chemical_formula_moiety         'C48 H72 O20 Si16'
_chemical_formula_sum            'C48 H72 O20 Si16'
_chemical_formula_weight         1418.50
_chemical_name_common            Octakis(trivinylsilyl)octasilicate
_space_group_IT_number           80
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  'I 4bw'
_symmetry_space_group_name_H-M   'I 41'
_atom_sites_solution_hydrogens   geom
_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                   21.1698(18)
_cell_length_b                   21.1698(18)
_cell_length_c                   16.059(3)
_cell_measurement_reflns_used    4937
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      28.20
_cell_measurement_theta_min      1.60
_cell_volume                     7197.0(16)
_computing_cell_refinement       'CrysAlis (Oxford Diffraction)'
_computing_data_collection       'CrysAlis (Oxford Diffraction)'
_computing_data_reduction        'CrysAlis (Oxford Diffraction)'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device       '\k-geometry diffractometer'
_diffrn_measurement_device_type  'Oxford Diffraction Xcalibur2'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0518
_diffrn_reflns_av_sigmaI/netI    0.0920
_diffrn_reflns_limit_h_max       29
_diffrn_reflns_limit_h_min       -29
_diffrn_reflns_limit_k_max       29
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            26352
_diffrn_reflns_theta_full        30.10
_diffrn_reflns_theta_max         30.10
_diffrn_reflns_theta_min         2.88
_diffrn_standards_decay_%        <2%
_diffrn_standards_interval_count 50
_diffrn_standards_number         2
_exptl_absorpt_coefficient_mu    0.345
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.309
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             2976
_exptl_crystal_size_max          0.12
_exptl_crystal_size_mid          0.11
_exptl_crystal_size_min          0.035
_refine_diff_density_max         1.154
_refine_diff_density_min         -0.332
_refine_ls_abs_structure_details
'Flack H D (1983), Acta Cryst. A39, 876-881, 5098 Friedel pairs'
_refine_ls_abs_structure_Flack   0.59(13)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.963
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     380
_refine_ls_number_reflns         10566
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.963
_refine_ls_R_factor_all          0.1067
_refine_ls_R_factor_gt           0.0597
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0571P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1168
_refine_ls_wR_factor_ref         0.1367
_reflns_number_gt                6414
_reflns_number_total             10566
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ws5065.cif
_cod_data_source_block           cs521
_cod_depositor_comments
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The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Tetragonal' changed to 'tetragonal'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Tetragonal' changed to 'tetragonal'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
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_cod_original_cell_volume        7197.2(16)
_cod_database_code               2104157