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_7032377
_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 N4 Si, 0.04(C14 H16), 0.84(C7 H8)'
_chemical_formula_sum            'C72.45 H87.35 N4 Si'
_chemical_formula_weight         1042.30
_chemical_name_systematic
;
 ?
;
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_symmetry_space_group_name_Hall  '-P 2ybc'
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_atom_sites_solution_hydrogens   geom
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_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Smart APEX II Ultra'
_diffrn_measurement_method       'omega scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
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_diffrn_reflns_theta_max         26.029
_diffrn_reflns_theta_min         1.343
_diffrn_source                   'INCOATEC Mo Microsource'
_exptl_absorpt_coefficient_mu    0.081
_exptl_absorpt_correction_T_max  0.7453
_exptl_absorpt_correction_T_min  0.6996
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_exptl_crystal_size_min          0.07
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_refine_diff_density_rms         0.041
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_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
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_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     850
_refine_ls_number_reflns         12433
_refine_ls_number_restraints     840
_refine_ls_restrained_S_all      1.015
_refine_ls_R_factor_all          0.0608
_refine_ls_R_factor_gt           0.0449
_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^)+(0.0425P)^2^+4.0936P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
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_reflns_Friedel_coverage         0.000
_reflns_number_gt                9816
_reflns_number_total             12433
_reflns_threshold_expression     'I > 2\s(I)'
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