Highly Active Magnesium Initiators for Ring-Opening Polymerization ofrac-Lactide
Wang, Liying; Ma, Haiyan; Macromolecules 43 (2010) 6535–; doi:10.1021/ma101263g

data_1502773
_publ_section_title
;
 Highly Active Magnesium Initiators for Ring-Opening Polymerization
 ofrac-Lactide
;
_journal_issue                   16
_journal_name_full               Macromolecules
_journal_page_first              6535
_journal_paper_doi               10.1021/ma101263g
_journal_volume                  43
_journal_year                    2010
_chemical_formula_sum            'C30 H53 Mg N3 O2 Si2'
_chemical_formula_weight         568.24
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 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                   13.032(4)
_cell_length_b                   14.817(5)
_cell_length_c                   17.543(6)
_cell_measurement_reflns_used    686
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      24.188
_cell_measurement_theta_min      2.698
_cell_volume                     3387.5(19)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SHELXTL'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0892
_diffrn_reflns_av_sigmaI/netI    0.1384
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            14128
_diffrn_reflns_theta_full        25.01
_diffrn_reflns_theta_max         25.01
_diffrn_reflns_theta_min         1.80
_diffrn_standards_decay_%        5.68
_exptl_absorpt_coefficient_mu    0.152
_exptl_absorpt_correction_T_max  0.9850
_exptl_absorpt_correction_T_min  0.9776
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.114
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             1240
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.187
_refine_diff_density_min         -0.170
_refine_diff_density_rms         0.031
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.08(12)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.744
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     356
_refine_ls_number_reflns         5976
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.744
_refine_ls_R_factor_all          0.1103
_refine_ls_R_factor_gt           0.0463
_refine_ls_shift/su_max          0.007
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0153P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0633
_refine_ls_wR_factor_ref         0.0735
_reflns_number_gt                2860
_reflns_number_total             5976
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ma101263g_si_001.cif
_cod_data_source_block           f90621d
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_cell_volume        3387.7(19)
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               1502773