Ytterbium amides of linked bis(amidinate): synthesis, molecular structures, and reactivity for the polymerization of l-lactide
Wang, Junfeng; Cai, Tao; Yao, Yingming; Zhang, Yong; Shen, Qi; Dalton Transactions  (2007) 5275–; doi:10.1039/b709310a

data_7006145
_publ_section_title
;
 Ytterbium amides of linked bis(amidinate): synthesis, molecular
 structures, and reactivity for the polymerization of l-lactide
;
_journal_issue                   45
_journal_name_full               'Dalton Transactions'
_journal_page_first              5275
_journal_paper_doi               10.1039/b709310a
_journal_year                    2007
_chemical_formula_moiety         'C35 H54 N5 O2 Si2 Yb'
_chemical_formula_sum            'C35 H54 N5 O2 Si2 Yb'
_chemical_formula_weight         806.05
_chemical_name_systematic
;
?
;
_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                 111.162(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   23.288(2)
_cell_length_b                   8.6725(7)
_cell_length_c                   20.4441(19)
_cell_measurement_reflns_used    11103
_cell_measurement_temperature    223(2)
_cell_measurement_theta_max      25.3
_cell_measurement_theta_min      3.0
_cell_volume                     3850.6(6)
_computing_cell_refinement       CrystalClear
_computing_data_collection       CrystalClear
_computing_data_reduction        CrystalStructure
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      223(2)
_diffrn_detector_area_resol_mean 7.31
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Rigaku Mercury'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71070
_diffrn_reflns_av_R_equivalents  0.0403
_diffrn_reflns_av_sigmaI/netI    0.0333
_diffrn_reflns_limit_h_max       28
_diffrn_reflns_limit_h_min       -27
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            36132
_diffrn_reflns_theta_full        25.35
_diffrn_reflns_theta_max         25.35
_diffrn_reflns_theta_min         3.01
_exptl_absorpt_coefficient_mu    2.526
_exptl_absorpt_correction_T_max  0.469
_exptl_absorpt_correction_T_min  0.264
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Jacobson, R. (1998) Private communication'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.390
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1652
_exptl_crystal_size_max          0.60
_exptl_crystal_size_mid          0.42
_exptl_crystal_size_min          0.30
_refine_diff_density_max         0.953
_refine_diff_density_min         -0.967
_refine_diff_density_rms         0.079
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.189
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     426
_refine_ls_number_reflns         7051
_refine_ls_number_restraints     2
_refine_ls_restrained_S_all      1.199
_refine_ls_R_factor_all          0.0605
_refine_ls_R_factor_gt           0.0477
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0317P)^2^+9.2846P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0945
_refine_ls_wR_factor_ref         0.0997
_reflns_number_gt                6010
_reflns_number_total             7051
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b709310a.txt
_cod_data_source_block           complexl
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               7006145