Star-Shaped Silacyclobutene-Containing π-Systems: Synthesis and Optical Properties
Liu, Junhui; Zhang, Shaoguang; Zhang, Wen-Xiong; Xi, Zhenfeng; Organometallics 28 (2009) 413–417; doi:10.1021/om800841s

data_4063505
_publ_section_title
;
 Star-Shaped Silacyclobutene-Containing \p-Systems: Synthesis and Optical
 Properties
;
_journal_issue                   2
_journal_name_full               Organometallics
_journal_page_first              413
_journal_page_last               417
_journal_paper_doi               10.1021/om800841s
_journal_volume                  28
_journal_year                    2009
_chemical_formula_sum            'C52 H54 Si2'
_chemical_formula_weight         735.13
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_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                 97.14(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   19.893(4)
_cell_length_b                   13.359(3)
_cell_length_c                   8.8375(18)
_cell_measurement_reflns_used    21414
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      27.48
_cell_measurement_theta_min      2.57
_cell_volume                     2330.4(9)
_computing_cell_refinement       Rapid-AUTO
_computing_data_collection       'Rapid-AUTO (Rigaku,2000)'
_computing_data_reduction        'CrystalStructure (Rigaku/MSC,2000)'
_computing_molecular_graphics    'Siemens SHELXTL V4.2,(Sheldrick,1990)'
_computing_publication_material  SHELXL-97,(Sheldrick,1997)
_computing_structure_refinement  SHELXL-97,(Sheldrick,1997)
_computing_structure_solution    SHELXS-97,(Sheldrick,1997)
_diffrn_ambient_temperature      298(2)
_diffrn_detector_area_resol_mean 10.00
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Rigaku RAXIS RAPID IP'
_diffrn_measurement_method       \W
_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  0.04715668
_diffrn_reflns_av_sigmaI/netI    0.1011
_diffrn_reflns_limit_h_max       25
_diffrn_reflns_limit_h_min       -25
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            21414
_diffrn_reflns_theta_full        27.48
_diffrn_reflns_theta_max         27.48
_diffrn_reflns_theta_min         2.57
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.107
_exptl_absorpt_correction_T_max  0.9583
_exptl_absorpt_correction_T_min  0.9384
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details
; 
                                  HIGASHI, T. (1995). Abscor-Empirical
                                  Absorption Correction based on Fourier
                                  Series Approximation.
                                  Rigaku Corporation,Tokyo,Japan.
;
_exptl_crystal_density_diffrn    1.048
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             788
_exptl_crystal_size_max          0.60
_exptl_crystal_size_mid          0.50
_exptl_crystal_size_min          0.40
_refine_diff_density_max         0.304
_refine_diff_density_min         -0.204
_refine_diff_density_rms         0.047
_refine_ls_extinction_coef       0.0293(18)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   0.993
_refine_ls_hydrogen_treatment    none
_refine_ls_matrix_type           full
_refine_ls_number_parameters     248
_refine_ls_number_reflns         5338
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.993
_refine_ls_R_factor_all          0.1407
_refine_ls_R_factor_gt           0.0573
_refine_ls_shift/su_max          0.004
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0480P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1284
_refine_ls_wR_factor_ref         0.1413
_reflns_number_gt                2046
_reflns_number_total             5338
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            om800841s_si_002.cif
_cod_data_source_block           z8611a
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_absorpt_correction_type' value 'Empirical' changed to
'empirical' according to the built-in table from CIF Core 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 
;
_cod_original_cell_volume        2330.5(8)
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               4063505