Cyclic and Bicyclic Methylpolysilanes and Some Oligosilanylene-Bridged Derivatives
Wallner, Andreas; Hlina, Johann; Konopa, Tina; Wagner, Harald; Baumgartner, Judith; Marschner, Christoph; Flörke, Ulrich; Organometallics 29 (2010) 2660–; doi:10.1021/om901104h

data_4067731
_publ_section_title
;
 Cyclic and Bicyclic Methylpolysilanes and Some Oligosilanylene-Bridged
 Derivatives
;
_journal_issue                   12
_journal_name_full               Organometallics
_journal_page_first              2660
_journal_paper_doi               10.1021/om901104h
_journal_volume                  29
_journal_year                    2010
_chemical_formula_sum            'C24 H72 Si12'
_chemical_formula_weight         697.89
_space_group_IT_number           29
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2ac'
_symmetry_space_group_name_H-M   'P c a 21'
_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            8
_cell_length_a                   24.391(5)
_cell_length_b                   19.863(4)
_cell_length_c                   18.147(4)
_cell_measurement_reflns_used    6623
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      51.614
_cell_measurement_theta_min      4.509
_cell_volume                     8792(3)
_computing_cell_refinement       'Bruker XSCANS'
_computing_data_collection       'Bruker XSCANS'
_computing_data_reduction        'Bruker SHELXTL'
_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 0.965
_diffrn_measured_fraction_theta_max 0.965
_diffrn_measurement_device_type  'SMART APEX'
_diffrn_measurement_method       '\w scans'
_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  0.0691
_diffrn_reflns_av_sigmaI/netI    0.0769
_diffrn_reflns_limit_h_max       32
_diffrn_reflns_limit_h_min       -31
_diffrn_reflns_limit_k_max       26
_diffrn_reflns_limit_k_min       -26
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            72642
_diffrn_reflns_theta_full        28.35
_diffrn_reflns_theta_max         28.35
_diffrn_reflns_theta_min         1.67
_exptl_absorpt_coefficient_mu    0.368
_exptl_absorpt_correction_T_max  0.8977
_exptl_absorpt_correction_T_min  0.8669
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.055
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       blocks
_exptl_crystal_F_000             3072
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.36
_exptl_crystal_size_min          0.30
_refine_diff_density_max         0.556
_refine_diff_density_min         -0.332
_refine_diff_density_rms         0.084
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.43(12)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.037
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     650
_refine_ls_number_reflns         20647
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.037
_refine_ls_R_factor_all          0.0790
_refine_ls_R_factor_gt           0.0566
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0552P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1154
_refine_ls_wR_factor_ref         0.1231
_reflns_number_gt                16295
_reflns_number_total             20647
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            om901104h_si_002.cif
_cod_data_source_block           6_654j
_cod_original_sg_symbol_H-M      Pca2(1)
_cod_database_code               4067731