Trinuclear and Tetranuclear Magnesium Alkoxide Clusters as Highly Active Initiators for Ring-Opening Polymerization of l-Lactide.
Gao, Yuan; Dai, Zhongran; Zhang, Jinjin; Ma, Xinxian; Tang, Ning; Wu, Jincai; Inorganic chemistry 53 (2014) 716–726; doi:10.1021/ic401459a

data_4337162
_publ_section_title
;
 Trinuclear and Tetranuclear Magnesium Alkoxide Clusters as Highly Active
 Initiators for Ring-Opening Polymerization of l-Lactide.
;
_journal_issue                   2
_journal_name_full               'Inorganic chemistry'
_journal_page_first              716
_journal_page_last               726
_journal_paper_doi               10.1021/ic401459a
_journal_volume                  53
_journal_year                    2014
_chemical_formula_moiety         'C44 H82  Mg3 N4  O6 '
_chemical_formula_sum            'C44 H82 Mg3 N4 O6'
_chemical_formula_weight         836.07
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_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                 108.324(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   16.8271(5)
_cell_length_b                   16.2974(4)
_cell_length_c                   19.0381(6)
_cell_measurement_reflns_used    6139
_cell_measurement_temperature    100.00(10)
_cell_measurement_theta_max      28.5182
_cell_measurement_theta_min      3.1639
_cell_volume                     4956.2(3)
_computing_cell_refinement
;
CrysAlisPro, Agilent Technologies,
Version 1.171.36.20 (release 27-06-2012 CrysAlis171 .NET)
(compiled Jul 11 2012,15:38:31)
;
_computing_data_collection
;
CrysAlisPro, Agilent Technologies,
Version 1.171.36.20 (release 27-06-2012 CrysAlis171 .NET)
(compiled Jul 11 2012,15:38:31)
;
_computing_data_reduction
;
CrysAlisPro, Agilent Technologies,
Version 1.171.36.20 (release 27-06-2012 CrysAlis171 .NET)
(compiled Jul 11 2012,15:38:31)
;
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100.00(10)
_diffrn_detector_area_resol_mean 16.0733
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'SuperNova, Dual, Cu at zero, Eos'
_diffrn_measurement_method       w/scans
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_source         'SuperNova (Mo) X-ray Source'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.7107
_diffrn_reflns_av_R_equivalents  0.0392
_diffrn_reflns_av_sigmaI/netI    0.0576
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -19
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            19541
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         3.17
_diffrn_standards_number         23819
_exptl_absorpt_coefficient_mu    0.107
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.97134
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro, Agilent Technologies,
Version 1.171.36.20 (release 27-06-2012 CrysAlis171 .NET)
(compiled Jul 11 2012,15:38:31)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.120
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1832
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.21
_refine_diff_density_max         0.263
_refine_diff_density_min         -0.238
_refine_diff_density_rms         0.048
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.025
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     562
_refine_ls_number_reflns         8695
_refine_ls_number_restraints     84
_refine_ls_restrained_S_all      1.021
_refine_ls_R_factor_all          0.0657
_refine_ls_R_factor_gt           0.0459
_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^)+(0.0318P)^2^+3.0161P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0969
_refine_ls_wR_factor_ref         0.1095
_reflns_number_gt                6686
_reflns_number_total             8695
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic401459a_si_001.cif
_cod_data_source_block           wujc_1122_1
_cod_original_cell_volume        4956.3(2)
_cod_original_formula_sum        'C44 H82  Mg3 N4  O6 '
_cod_database_code               4337162