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_7031749
_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'
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_cell_angle_gamma                90
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_cell_measurement_theta_min      2.365
_cell_volume                     7060.5(16)
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_diffrn_measurement_device_type  'BRUKER SMART APEXII ULTRA'
_diffrn_measurement_method       omega-scans
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
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_diffrn_reflns_av_unetI/netI     0.0138
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_diffrn_reflns_point_group_measured_fraction_full 1.000
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_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
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_refine_ls_abs_structure_details
;
 Refined as an inversion twin.
;
_refine_ls_abs_structure_Flack   0.188(15)
_refine_ls_extinction_method     none
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_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'
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_reflns_number_gt                13722
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_reflns_threshold_expression     'I > 2\s(I)'
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'Adding full bibliography for 7031746--7031749.cif.'
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