Iron-Amide-Sulfide and Iron-Imide-Sulfide Clusters: Heteroligated Core Environments Relevant to the Nitrogenase FeMo Cofactor
Xu-Dong Chen; Wei Zhang; Jeremiah S. Duncan; Sonny C. Lee; Inorganic Chemistry 51 (2012) 12891–12904; doi:10.1021/ic301868m

data_4331174
_publ_contact_author_address
;                                                                               
 Department of Chemistry
 University of Waterloo
 200 University Avenue West
 Waterloo, Ontario  N2L 3G1
 CANADA  
;
_publ_contact_author_email       sclee@uwaterloo.ca
_publ_contact_author_fax         519-746-0435
_publ_contact_author_name        'Sonny C. Lee'
_publ_contact_author_phone       '519-885-1211 x37501'
_publ_section_title
;
 Iron-Amide-Sulfide and Iron-Imide-Sulfide Clusters: Heteroligated Core
 Environments Relevant to the Nitrogenase FeMo Cofactor
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              12891
_journal_page_last               12904
_journal_paper_doi               10.1021/ic301868m
_journal_volume                  51
_journal_year                    2012
_chemical_compound_source        'Chemical synthesis, S.C. Lee lab'
_chemical_formula_moiety         '(Fe 2+)2 (C4H10N -)2 (C6H18NSi2 1-)2'
_chemical_formula_structural     Fe2(NC4H10)2(NSi2C6H18)2
_chemical_formula_sum            'C20 H56 Fe2 N4 Si4'
_chemical_formula_weight         576.75
_chemical_name_common            Fe2(mu-NHtBu)[N(TMS)2]2
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL
_cell_angle_alpha                90.00
_cell_angle_beta                 102.368(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   11.7818(7)
_cell_length_b                   9.5043(6)
_cell_length_c                   15.9211(8)
_cell_measurement_reflns_used    6729
_cell_measurement_temperature    200(2)
_cell_measurement_theta_max      23.97
_cell_measurement_theta_min      1.77
_cell_volume                     1741.43(18)
_computing_cell_refinement       DENZO-SMN
_computing_data_collection       'NONIUS COLLECT'
_computing_data_reduction        DENZO-SMN
_computing_molecular_graphics    'Siemens SHELXTL'
_computing_publication_material  'CIFTAB, Siemens SHELXTL'
_computing_structure_refinement  'SHELXL-93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS-86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      200(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device       'Nonius KappaCCD'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.042
_diffrn_reflns_av_sigmaI/netI    0.0476
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            6729
_diffrn_reflns_theta_full        23.97
_diffrn_reflns_theta_max         23.97
_diffrn_reflns_theta_min         1.77
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.983
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            green
_exptl_crystal_density_diffrn    1.100
_exptl_crystal_description       rods
_exptl_crystal_F_000             624
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.33
_exptl_crystal_size_min          0.23
_refine_diff_density_max         0.715
_refine_diff_density_min         -0.333
_refine_diff_density_rms         0.060
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_all   1.065
_refine_ls_goodness_of_fit_obs   1.133
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     234
_refine_ls_number_reflns         2718
_refine_ls_number_restraints     126
_refine_ls_restrained_S_all      1.062
_refine_ls_restrained_S_obs      1.122
_refine_ls_R_factor_all          0.0753
_refine_ls_R_factor_obs          0.0484
_refine_ls_shift/esd_max         0.000
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0779P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.1405
_refine_ls_wR_factor_obs         0.1238
_reflns_number_observed          1937
_reflns_number_total             2719
_reflns_observed_criterion       I>2\s(I)
_cod_data_source_file            ic301868m_si_002_2.cif
_cod_data_source_block           574_14
_cod_original_cell_volume        1741.4(2)
_cod_database_code               4331174