Isolable p- and m-[(tBu2MeSi)2Si]2C6H4: Disilaquinodimethane vs Triplet Bis(silyl radical)
Takeshi Nozawa; Michiyo Nagata; Masaaki Ichinohe; Akira Sekiguchi; Journal of the American Chemical Society 133 (2011) 5773–5775; doi:10.1021/ja2014746

data_4106001
_publ_section_title
;
 Isolable p- and m-[(tBu2MeSi)2Si]2C6H4: Disilaquinodimethane vs Triplet
 Bis(silyl radical)
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              5773
_journal_page_last               5775
_journal_paper_doi               10.1021/ja2014746
_journal_volume                  133
_journal_year                    2011
_chemical_formula_sum            'C42 H88 Si6'
_chemical_formula_weight         761.66
_chemical_name_systematic
; 
 1,3-Bis[2,2-di-tert-butyl-1-(di-tert-butylmethylsilyl)-
 2-methyldisilanyl]benzene-1',1''-diyl 
;
_space_group_IT_number           56
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ab 2ac'
_symmetry_space_group_name_H-M   'P c c n'
_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                   26.2010(11)
_cell_length_b                   12.1560(6)
_cell_length_c                   15.404(2)
_cell_measurement_reflns_used    37452
_cell_measurement_temperature    150.0(1)
_cell_measurement_theta_max      25.36
_cell_measurement_theta_min      2.27
_cell_volume                     4906.2(7)
_computing_cell_refinement       'HKL scalepack'
_computing_data_collection       'MacScience Xpress'
_computing_data_reduction        Denzo
_computing_molecular_graphics    ORTEP
_computing_publication_material  CIFTAB
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    SIR92
_diffrn_ambient_temperature      150.0(1)
_diffrn_measured_fraction_theta_full 0.945
_diffrn_measured_fraction_theta_max 0.945
_diffrn_measurement_device       'MacScience DIP2030 Image plate'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'rotating anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71070
_diffrn_reflns_av_R_equivalents  0.1680
_diffrn_reflns_av_sigmaI/netI    0.0733
_diffrn_reflns_limit_h_max       31
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            37452
_diffrn_reflns_theta_full        25.36
_diffrn_reflns_theta_max         25.36
_diffrn_reflns_theta_min         2.27
_exptl_absorpt_coefficient_mu    0.196
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            Yellow
_exptl_crystal_density_diffrn    1.031
_exptl_crystal_description       Plate
_exptl_crystal_F_000             1696
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.02
_refine_diff_density_max         0.553
_refine_diff_density_min         -0.342
_refine_diff_density_rms         0.072
_refine_ls_extinction_coef       0.0004(4)
_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   1.034
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     217
_refine_ls_number_reflns         4261
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.034
_refine_ls_R_factor_all          0.1035
_refine_ls_R_factor_gt           0.0621
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0918P)^2^+0.5323P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1492
_refine_ls_wR_factor_ref         0.1685
_reflns_number_gt                2774
_reflns_number_total             4261
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja2014746_si_002.cif
_cod_data_source_block           meta-Si2quinodimethane
_cod_original_cell_volume        4906.2(8)
_cod_original_sg_symbol_H-M      'P c c n '
_cod_database_code               4106001