Bimetallic lanthanide amido complexes as highly active initiators for the ring-opening polymerization of lactides.
Sun, Song; Nie, Kun; Tan, Yufang; Zhao, Bei; Zhang, Yong; Shen, Qi; Yao, Yingming; Dalton transactions (Cambridge, England : 2003) 42 (2013) 2870–2878; doi:10.1039/c2dt31597a

data_7022076
_publ_section_title
;
 Bimetallic lanthanide amido complexes as highly active initiators for the
 ring-opening polymerization of lactides.
;
_journal_issue                   8
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              2870
_journal_page_last               2878
_journal_paper_doi               10.1039/c2dt31597a
_journal_volume                  42
_journal_year                    2013
_chemical_formula_moiety         'C64 H124 N8 Si8 Sm2, 2(C7 H8)'
_chemical_formula_sum            'C78 H140 N8 Si8 Sm2'
_chemical_formula_weight         1715.40
_space_group_IT_number           33
_symmetry_cell_setting           orthorhombic
_symmetry_Int_Tables_number      33
_symmetry_space_group_name_Hall  'P 2c -2n'
_symmetry_space_group_name_H-M   'P n a 21'
_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                90.00
_cell_formula_units_Z            4
_cell_length_a                   19.569(3)
_cell_length_b                   13.4929(13)
_cell_length_c                   35.129(3)
_cell_measurement_reflns_used    24526
_cell_measurement_temperature    223(2)
_cell_measurement_theta_max      27.5
_cell_measurement_theta_min      3.0
_cell_volume                     9275.6(19)
_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 0.990
_diffrn_measured_fraction_theta_max 0.990
_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  0.0566
_diffrn_reflns_av_sigmaI/netI    0.1165
_diffrn_reflns_limit_h_max       23
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       35
_diffrn_reflns_limit_l_min       -42
_diffrn_reflns_number            27156
_diffrn_reflns_theta_full        25.50
_diffrn_reflns_theta_max         25.50
_diffrn_reflns_theta_min         3.10
_exptl_absorpt_coefficient_mu    1.398
_exptl_absorpt_correction_T_max  0.819
_exptl_absorpt_correction_T_min  0.542
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Jacobson, R. (1998) Private communication'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.228
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       platelet
_exptl_crystal_F_000             3600
_exptl_crystal_size_max          0.70
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.15
_refine_diff_density_max         3.039
_refine_diff_density_min         -0.996
_refine_diff_density_rms         0.121
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.30(3)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.055
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     811
_refine_ls_number_reflns         14571
_refine_ls_number_restraints     13
_refine_ls_restrained_S_all      1.055
_refine_ls_R_factor_all          0.1015
_refine_ls_R_factor_gt           0.0802
_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^)+(0.0735P)^2^+27.4633P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1743
_refine_ls_wR_factor_ref         0.1914
_reflns_number_gt                11355
_reflns_number_total             14571
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c2dt31597a.txt
_cod_data_source_block           complex2
_cod_original_cell_volume        9275.7(18)
_cod_database_code               7022076