Controlled synthesis of mononuclear or binuclear aryloxo ytterbium complexes supported by beta-diketiminate ligand and their activity for polymerization of epsilon-caprolactone and L-lactide.
Chen, Hongxia; Liu, Peng; Yao, Haisheng; Zhang, Yong; Yao, Yingming; Shen, Qi; Dalton transactions (Cambridge, England : 2003) 39 (2010) 6877–6885; doi:10.1039/c002385j

data_7025627
_publ_section_title
;
 Controlled synthesis of mononuclear or binuclear aryloxo ytterbium
 complexes supported by beta-diketiminate ligand and their activity for
 polymerization of epsilon-caprolactone and L-lactide.
;
_journal_issue                   29
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              6877
_journal_page_last               6885
_journal_paper_doi               10.1039/c002385j
_journal_volume                  39
_journal_year                    2010
_chemical_formula_moiety         'C53 H75 N2 O2 Yb'
_chemical_formula_sum            'C53 H75 N2 O2 Yb'
_chemical_formula_weight         945.19
_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                 113.766(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   21.0121(19)
_cell_length_b                   12.0067(9)
_cell_length_c                   21.050(2)
_cell_measurement_reflns_used    21301
_cell_measurement_temperature    223(2)
_cell_measurement_theta_max      27.5
_cell_measurement_theta_min      3.0
_cell_volume                     4860.3(7)
_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 14.63
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type  'Rigaku Saturn'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71075
_diffrn_reflns_av_R_equivalents  0.0465
_diffrn_reflns_av_sigmaI/netI    0.0645
_diffrn_reflns_limit_h_max       25
_diffrn_reflns_limit_h_min       -23
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            24447
_diffrn_reflns_theta_full        25.50
_diffrn_reflns_theta_max         25.50
_diffrn_reflns_theta_min         3.03
_exptl_absorpt_coefficient_mu    1.964
_exptl_absorpt_correction_T_max  0.675
_exptl_absorpt_correction_T_min  0.498
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Jacobson, R. (1998) Private communication'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.292
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             1972
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.20
_refine_diff_density_max         1.458
_refine_diff_density_min         -1.062
_refine_diff_density_rms         0.100
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.168
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     506
_refine_ls_number_reflns         8998
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.168
_refine_ls_R_factor_all          0.0691
_refine_ls_R_factor_gt           0.0574
_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^)+(0.0336P)^2^+8.0604P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1099
_refine_ls_wR_factor_ref         0.1155
_reflns_number_gt                7756
_reflns_number_total             8998
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c002385j.txt
_cod_data_source_block           complex2
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               7025627