Geometrically Compelled Disilene with λ<sup>4</sup>-Coordinate Si<sup>II</sup> Atoms.
Kostenko, Arseni; Driess, Matthias; Journal of the American Chemical Society 140 (2018) 16962–16966; doi:10.1021/jacs.8b11393

data_4133584
_publ_section_title
;
 Geometrically Compelled Disilene with \l<sup>4</sup>-Coordinate
 Si<sup>II</sup> Atoms.
;
_journal_issue                   49
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              16962
_journal_page_last               16966
_journal_paper_doi               10.1021/jacs.8b11393
_journal_volume                  140
_journal_year                    2018
_chemical_formula_moiety         'C44 H58 N4 Si2'
_chemical_formula_sum            'C44 H58 N4 Si2'
_chemical_formula_weight         699.12
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2yn'
_space_group_name_H-M_alt        'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     heavy
_atom_sites_solution_secondary   difmap
_audit_creation_date             2018-10-04
_audit_creation_method
;
Olex2 1.2
(compiled 2018.05.29 svn.r3508 for OlexSys, GUI svn.r5506)
;
_cell_angle_alpha                90.00
_cell_angle_beta                 96.968(13)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   9.1557(14)
_cell_length_b                   35.740(4)
_cell_length_c                   12.4628(19)
_cell_measurement_reflns_used    1245
_cell_measurement_temperature    150.00(10)
_cell_measurement_theta_max      50.6000
_cell_measurement_theta_min      3.7460
_cell_volume                     4048.0(10)
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'ShelXH-1997 (Sheldrick, 2008)'
_computing_structure_solution    'ShelXS (Sheldrick, 2008)'
_diffrn_ambient_temperature      150.00(10)
_diffrn_measured_fraction_theta_full 0.971
_diffrn_measured_fraction_theta_max 0.971
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'SuperNova, Single source at offset, Atlas'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.2228
_diffrn_reflns_av_unetI/netI     0.1969
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       44
_diffrn_reflns_limit_k_min       -40
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            29141
_diffrn_reflns_theta_full        74.32
_diffrn_reflns_theta_max         74.32
_diffrn_reflns_theta_min         3.78
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    1.050
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.21231
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.38.46 (Rigaku Oxford Diffraction, 2015)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_density_diffrn    1.147
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       rod
_exptl_crystal_F_000             1512
_refine_diff_density_max         0.325
_refine_diff_density_min         -0.466
_refine_diff_density_rms         0.066
_refine_ls_extinction_coef       0.00030(8)
_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   0.966
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     480
_refine_ls_number_reflns         8035
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.966
_refine_ls_R_factor_all          0.2076
_refine_ls_R_factor_gt           0.0884
_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^)+(0.0602P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1750
_refine_ls_wR_factor_ref         0.2483
_reflns_number_gt                3134
_reflns_number_total             8035
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja8b11393_si_003.cif
_cod_data_source_block           cu-2883
_cod_database_code               4133584
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2.a Secondary CH2 refined with riding coordinates:
 C6(H6A,H6B), C7AA(H7AA,H7AB)
2.b Aromatic/amide H refined with riding coordinates:
 C8(H8), C1AA(H1AA), C0AA(H0AA), C9(H9), C13(H13), C9AA(H9AA), C0BA(H0BA),
 C11(H11), C1BA(H1BA), C14(H14), C2BA(H2BA), C3BA(H3BA), C10(H10), C6CA(H6CA)
2.c Idealised Me refined as rotating group:
 C6AA(H6AA,H6AB,H6AC), C18(H18A,H18B,H18C), C6BA(H6BA,H6BB,H6BC), C0CA(H0CA,
 H0CB,H0CC), C1CA(H1CA,H1CB,H1CC), C8BA(H8BA,H8BB,H8BC), C7BA(H7BA,H7BB,H7BC),
 C4BA(H4BA,H4BB,H4BC), C5BA(H5BA,H5BB,H5BC), C9BA(H9BA,H9BB,H9BC), C3CA(H3CA,
 H3CB,H3CC), C2CA(H2CA,H2CB,H2CC)
;
_olex2_submission_special_instructions 'No special instructions were received'