Halo, Alkyl, Aryl, and Bis(imido) Complexes of Niobium Supported by the beta-Diketiminato Ligand.
Tomson, Neil C.; Arnold, John; Bergman, Robert G.; Organometallics 29 (2010) 2926–2942; doi:10.1021/om1001827

data_4065888
_publ_section_title
;
 Halo, Alkyl, Aryl, and Bis(imido) Complexes of Niobium Supported by the
 beta-Diketiminato Ligand.
;
_journal_issue                   13
_journal_name_full               Organometallics
_journal_page_first              2926
_journal_page_last               2942
_journal_paper_doi               10.1021/om1001827
_journal_volume                  29
_journal_year                    2010
_chemical_formula_moiety         'C38 H55 Cl2 N4 Nb'
_chemical_formula_sum            'C38 H55 Cl2 N4 Nb'
_chemical_formula_weight         731.67
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      14
_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-97
_cell_angle_alpha                90.00
_cell_angle_beta                 99.7920(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.8653(8)
_cell_length_b                   17.9863(17)
_cell_length_c                   24.392(2)
_cell_measurement_reflns_used    5117
_cell_measurement_temperature    136(2)
_cell_measurement_theta_max      49.301
_cell_measurement_theta_min      6.615
_cell_volume                     3832.7(6)
_computing_cell_refinement       'Bruker SAINT v7.07'
_computing_data_collection       'Bruker SMART v5.054d'
_computing_data_reduction        'Bruker SAINT v7.07'
_computing_molecular_graphics    'Bruker-AXS XP v.6'
_computing_publication_material  'Bruker-AXS XP v.6'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      136(2)
_diffrn_measured_fraction_theta_full 0.994
_diffrn_measured_fraction_theta_max 0.994
_diffrn_measurement_device_type  'SMART 1000'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0291
_diffrn_reflns_av_sigmaI/netI    0.0531
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            16890
_diffrn_reflns_theta_full        24.70
_diffrn_reflns_theta_max         24.70
_diffrn_reflns_theta_min         3.31
_diffrn_source                   'fine-focus sealed tube'
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.484
_exptl_absorpt_correction_T_max  1
_exptl_absorpt_correction_T_min  0.917772
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'Blessing, 1995'
_exptl_crystal_colour            red
_exptl_crystal_density_diffrn    1.268
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1544
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.23
_exptl_crystal_size_min          0.17
_refine_diff_density_max         1.014
_refine_diff_density_min         -0.399
_refine_diff_density_rms         0.067
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.206
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     406
_refine_ls_number_reflns         6495
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.206
_refine_ls_R_factor_all          0.0531
_refine_ls_R_factor_gt           0.0367
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0367P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0872
_refine_ls_wR_factor_ref         0.0932
_reflns_number_gt                5096
_reflns_number_total             6495
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            om1001827_si_002.cif
_cod_data_source_block           (BDI)pyCl2Nb(NtBu)
_cod_original_cell_volume        3832.8(6)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               4065888