Isolobal Zwitterionic Niobium and Tantalum Imido and Zirconium Monocyclopentadienyl Complexes: Theoretical and Methyl Methacrylate Polymerization Studies
Arteaga-Müller, Rocío; Sánchez-Nieves, Javier; Ramos, Javier; Royo, Pascual; Mosquera, Marta E. G.; Organometallics 27 (2008) 1417–; doi:10.1021/om701068h

data_4070839
_publ_section_title
;
 Isolobal Zwitterionic Niobium and Tantalum Imido and Zirconium
 Monocyclopentadienyl Complexes: Theoretical and Methyl Methacrylate
 Polymerization Studies
;
_journal_issue                   7
_journal_name_full               Organometallics
_journal_page_first              1417
_journal_paper_doi               10.1021/om701068h
_journal_volume                  27
_journal_year                    2008
_chemical_absolute_configuration unk
_chemical_compound_source        'synthesis as described'
_chemical_formula_moiety         'C25 H30 N1 Nb1'
_chemical_formula_sum            'C25 H30 N Nb'
_chemical_formula_weight         437.41
_chemical_name_systematic
;
 ?
;
_space_group_IT_number           159
_symmetry_cell_setting           trigonal
_symmetry_Int_Tables_number      159
_symmetry_space_group_name_Hall  'P 3 -2c'
_symmetry_space_group_name_H-M   'P 3 1 c'
_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                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            2
_cell_length_a                   11.2683(13)
_cell_length_b                   11.2683(14)
_cell_length_c                   10.2514(11)
_cell_measurement_reflns_used    41
_cell_measurement_temperature    200(2)
_cell_measurement_theta_max      19.488
_cell_measurement_theta_min      4.451
_cell_volume                     1127.3(2)
_computing_cell_refinement
'Dirax/lsq (Duisenberg & Schreurs, 1989-2000)'
_computing_data_collection       'Collect (Nonius BV, 1997-2000)'
_computing_data_reduction        'EvalCCD (Duisenberg & Schreurs 1990-2000)'
_computing_molecular_graphics    'Ortep-3 for Windows (Farrugia, 1997)'
_computing_publication_material  'WinGX publication routines (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-86 (Sheldrick, 1986)'
_diffrn_ambient_temperature      200(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_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  0.0868
_diffrn_reflns_av_sigmaI/netI    0.0507
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            24889
_diffrn_reflns_theta_full        27.49
_diffrn_reflns_theta_max         27.49
_diffrn_reflns_theta_min         3.62
_exptl_absorpt_coefficient_mu    0.542
_exptl_absorpt_correction_T_max  0.918
_exptl_absorpt_correction_T_min  0.749
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
 R.H. Blessing, Acta Cryst. (1995), A51, 33-38
;
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.289
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             456
_exptl_crystal_size_max          0.217
_exptl_crystal_size_mid          0.185
_exptl_crystal_size_min          0.159
_refine_diff_density_max         0.190
_refine_diff_density_min         -0.284
_refine_diff_density_rms         0.048
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.05(5)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.999
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     82
_refine_ls_number_reflns         1724
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.999
_refine_ls_R_factor_all          0.0497
_refine_ls_R_factor_gt           0.0327
_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^)+(0.0254P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0557
_refine_ls_wR_factor_ref         0.0593
_reflns_number_gt                1427
_reflns_number_total             1724
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            om701068h-file001.cif
_cod_data_source_block           3a
_cod_database_code               4070839