Bridged Bis(amidinate) Ytterbium Alkoxide and Phenoxide: Syntheses, Structures, and Their High Activity for Controlled Polymerization of l-Lactide and ε-Caprolactone
Junfeng Wang; Yingming Yao; Yong Zhang; Qi Shen; Inorganic Chemistry 48 (2009) 744–751; doi:10.1021/ic801189j

data_4301186
_publ_section_title
;
Bridged Bis(amidinate) Ytterbium Alkoxide and Phenoxide: Syntheses,
Structures, and Their High Activity for Controlled Polymerization
of l-Lactide and \e-Caprolactone
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              744
_journal_page_last               751
_journal_paper_doi               10.1021/ic801189j
_journal_volume                  48
_journal_year                    2009
_chemical_formula_moiety         'C52 H82 N8 O2 Si4 Yb2'
_chemical_formula_sum            'C52 H82 N8 O2 Si4 Yb2'
_chemical_formula_weight         1309.70
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_Int_Tables_number      2
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                109.501(9)
_cell_angle_beta                 99.684(9)
_cell_angle_gamma                104.004(12)
_cell_formula_units_Z            1
_cell_length_a                   10.5426(3)
_cell_length_b                   10.7834(5)
_cell_length_c                   15.2118(6)
_cell_measurement_reflns_used    6474
_cell_measurement_temperature    193(2)
_cell_measurement_theta_max      25.3
_cell_measurement_theta_min      3.0
_cell_volume                     1522.0(2)
_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      193(2)
_diffrn_detector_area_resol_mean 7.31
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_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  0.0300
_diffrn_reflns_av_sigmaI/netI    0.0366
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            15165
_diffrn_reflns_theta_full        25.35
_diffrn_reflns_theta_max         25.35
_diffrn_reflns_theta_min         3.02
_exptl_absorpt_coefficient_mu    3.174
_exptl_absorpt_correction_T_max  0.7419
_exptl_absorpt_correction_T_min  0.4494
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Jacobson, R. (1998) Private communication'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.429
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             662
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.10
_refine_diff_density_max         1.280
_refine_diff_density_min         -1.198
_refine_diff_density_rms         0.101
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.125
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     316
_refine_ls_number_reflns         5525
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.125
_refine_ls_R_factor_all          0.0301
_refine_ls_R_factor_gt           0.0269
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0314P)^2^+0.2324P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0618
_refine_ls_wR_factor_ref         0.0636
_reflns_number_gt                5181
_reflns_number_total             5525
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic801189j_si_001_2.cif
_cod_data_source_block           complex2
_cod_original_cell_volume        1521.96(10)
_cod_original_sg_symbol_Hall     '-p 1'
_cod_database_code               4301186