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_4337161
_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         'C26 H51 Mg2 N3 O4,C6'
_chemical_formula_sum            'C32 H51 Mg2 N3 O4'
_chemical_formula_weight         590.37
_chemical_name_systematic
;
 ?
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_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2yn'
_space_group_name_H-M_alt        'P 1 21/n 1'
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_atom_sites_solution_hydrogens   mixed
_audit_creation_method           SHELXL-2013
_cell_angle_alpha                90
_cell_angle_beta                 110.246(5)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   13.6279(6)
_cell_length_b                   18.2570(6)
_cell_length_c                   14.4482(6)
_cell_measurement_reflns_used    7456
_cell_measurement_temperature    100.3(5)
_cell_measurement_theta_max      72.4776
_cell_measurement_theta_min      3.2575
_cell_volume                     3372.7(3)
_computing_cell_refinement
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CrysAlisPro, Agilent Technologies,
Version 1.171.36.20 (release 27-06-2012 CrysAlis171 .NET)
(compiled Jul 11 2012,15:38:31)
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_computing_data_collection
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CrysAlisPro, Agilent Technologies,
Version 1.171.36.20 (release 27-06-2012 CrysAlis171 .NET)
(compiled Jul 11 2012,15:38:31)
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_computing_data_reduction
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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      100.3(5)
_diffrn_detector_area_resol_mean 16.0733
_diffrn_measured_fraction_theta_full 0.981
_diffrn_measured_fraction_theta_max 0.979
_diffrn_measurement_device_type  'SuperNova, Dual, Cu at zero, Eos'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_source         'SuperNova (Cu) X-ray Source'
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.5418
_diffrn_reflns_av_R_equivalents  0.0270
_diffrn_reflns_av_unetI/netI     0.0273
_diffrn_reflns_Laue_measured_fraction_full 0.981
_diffrn_reflns_Laue_measured_fraction_max 0.979
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            18810
_diffrn_reflns_point_group_measured_fraction_full 0.981
_diffrn_reflns_point_group_measured_fraction_max 0.979
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         72.629
_diffrn_reflns_theta_min         4.062
_exptl_absorpt_coefficient_mu    0.933
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.77223
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
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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    1.163
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1280
_exptl_crystal_size_max          0.2000
_exptl_crystal_size_mid          0.0800
_exptl_crystal_size_min          0.0600
_refine_diff_density_max         0.982
_refine_diff_density_min         -1.234
_refine_diff_density_rms         0.084
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.066
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     392
_refine_ls_number_reflns         6561
_refine_ls_number_restraints     16
_refine_ls_restrained_S_all      1.119
_refine_ls_R_factor_all          0.0785
_refine_ls_R_factor_gt           0.0701
_refine_ls_shift/su_max          0.138
_refine_ls_shift/su_mean         0.003
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
;
 w=1/[\s^2^(Fo^2^)+(0.1112P)^2^+4.1778P]
 where P=(Fo^2^+2Fc^2^)/3
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1930
_refine_ls_wR_factor_ref         0.2027
_reflns_Friedel_coverage         0.000
_reflns_number_gt                5667
_reflns_number_total             6561
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ic401459a_si_001.cif
_cod_data_source_block           gy1
_cod_database_code               4337161