Synthesis and structural investigation of R2Si (R = Me, Ph) bridged di-N-heterocyclic carbenes.
Ghadwal, Rajendra S.; Reichmann, Sven O.; Carl, Elena; Herbst-Irmer, Regine; Dalton transactions (Cambridge, England : 2003) 43 (2014) 13704–13710; doi:10.1039/c4dt01681e

data_7032380
_publ_section_title
;
 Synthesis and structural investigation of R2Si (R = Me, Ph) bridged
 di-N-heterocyclic carbenes.
;
_journal_issue                   36
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              13704
_journal_page_last               13710
_journal_paper_doi               10.1039/c4dt01681e
_journal_volume                  43
_journal_year                    2014
_chemical_formula_moiety         'C66 H80 Cl2 Cu2 N4 Si, 3(C H2 Cl2)'
_chemical_formula_sum            'C69 H86 Cl8 Cu2 N4 Si'
_chemical_formula_weight         1410.18
_chemical_name_systematic
;
 ?
;
_space_group_crystal_system      orthorhombic
_space_group_IT_number           33
_space_group_name_Hall           'P 2c -2n'
_space_group_name_H-M_alt        'P n a 21'
_symmetry_space_group_name_Hall  'P 2c -2n'
_symmetry_space_group_name_H-M   'P n a 21'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2013
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   24.735(3)
_cell_length_b                   11.999(2)
_cell_length_c                   23.789(2)
_cell_measurement_reflns_used    9919
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      26.328
_cell_measurement_theta_min      2.365
_cell_volume                     7060.5(16)
_computing_cell_refinement       'SAINT v7.68A'
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_computing_data_reduction        'SAINT v7.68A'
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_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'BRUKER SMART APEXII ULTRA'
_diffrn_measurement_method       omega-scans
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0340
_diffrn_reflns_av_unetI/netI     0.0138
_diffrn_reflns_Laue_measured_fraction_full 1.000
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_diffrn_reflns_limit_h_min       -30
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_diffrn_reflns_limit_k_min       -14
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_diffrn_reflns_limit_l_min       -29
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_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 1.000
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         26.347
_diffrn_reflns_theta_min         1.647
_diffrn_source                   'rotating anode'
_exptl_absorpt_coefficient_mu    0.964
_exptl_absorpt_correction_T_max  0.7454
_exptl_absorpt_correction_T_min  0.6803
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS-2012/1
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.327
_exptl_crystal_description       plate
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_exptl_crystal_size_max          0.368
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_refine_diff_density_rms         0.064
_refine_ls_abs_structure_details
;
 Refined as an inversion twin.
;
_refine_ls_abs_structure_Flack   0.188(15)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.075
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
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_refine_ls_number_reflns         14390
_refine_ls_number_restraints     2847
_refine_ls_restrained_S_all      1.076
_refine_ls_R_factor_all          0.0373
_refine_ls_R_factor_gt           0.0352
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0466P)^2^+8.3246P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0955
_refine_ls_wR_factor_ref         0.0968
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_reflns_Friedel_fraction_full    1.000
_reflns_Friedel_fraction_max     1.000
_reflns_number_gt                13722
_reflns_number_total             14390
_reflns_threshold_expression     'I > 2\s(I)'
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_shelxl_version_number           2013-4
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_shelx_hkl_checksum              67933