Different mechanisms at different temperatures for the ring-opening polymerization of lactide catalyzed by binuclear magnesium and zinc alkoxides.
Sun, Yangyang; Cui, Yaqin; Xiong, Jiao; Dai, Zhongran; Tang, Ning; Wu, Jincai; Dalton transactions (Cambridge, England : 2003) 44 (2015) 16383–16391; doi:10.1039/c5dt01784j

data_7036168
_publ_section_title
;
 Different mechanisms at different temperatures for the ring-opening
 polymerization of lactide catalyzed by binuclear magnesium and zinc
 alkoxides.
;
_journal_issue                   37
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              16383
_journal_page_last               16391
_journal_paper_doi               10.1039/c5dt01784j
_journal_volume                  44
_journal_year                    2015
_chemical_formula_moiety         'C58 H82 Mg2 N4 O4, C3.5 H4, 2(C3 H3)'
_chemical_formula_sum            'C67.5 H92 Mg2 N4 O4'
_chemical_formula_weight         1072.07
_chemical_name_systematic
;
 ? 
;
_space_group_crystal_system      orthorhombic
_space_group_IT_number           56
_space_group_name_Hall           '-P 2ab 2ac'
_space_group_name_H-M_alt        'P c c n'
_symmetry_space_group_name_Hall  '-P 2ab 2ac'
_symmetry_space_group_name_H-M   'P c c n'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     iterative
_atom_sites_solution_secondary   difmap
_audit_creation_date             2015-05-11
_audit_creation_method
;
Olex2 1.2
(compiled 2015.01.26 svn.r3150 for OlexSys, GUI svn.r4998)
;
_audit_update_record
;
2015-05-11 deposited with the CCDC.
2015-08-14 downloaded from the CCDC.
;
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   29.2813(9)
_cell_length_b                   21.6214(8)
_cell_length_c                   20.7411(6)
_cell_measurement_reflns_used    9051
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      25.7710
_cell_measurement_theta_min      3.4330
_cell_volume                     13131.2(7)
_computing_cell_refinement
;
CrysAlisPro, Agilent Technologies,
Version 1.171.36.28 (release 01-02-2013 CrysAlis171 .NET)
(compiled Feb  1 2013,16:14:44)
;
_computing_data_collection
;
CrysAlisPro, Agilent Technologies,
Version 1.171.36.28 (release 01-02-2013 CrysAlis171 .NET)
(compiled Feb  1 2013,16:14:44)
;
_computing_data_reduction
;
CrysAlisPro, Agilent Technologies,
Version 1.171.36.28 (release 01-02-2013 CrysAlis171 .NET)
(compiled Feb  1 2013,16:14:44)
;
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'XL (Sheldrick, 2008)'
_computing_structure_solution
;
Superflip (Palatinus & Chapuis, 2007;Palatinus & van der Lee, 2008;
Palatinus et al., 2012)
;
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean 16.0733
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_details
;
  1 omega  -99.00  -71.40   1.2000   14.0000
omega____ theta____ kappa____ phi______ frames
    -      -19.5262  178.0000  120.0000 23

  2 omega  -84.00    0.00   1.2000   14.0000
omega____ theta____ kappa____ phi______ frames
    -      -19.5262  -57.0000 -180.0000 70

  3 omega  -19.00   17.00   1.2000   14.0000
omega____ theta____ kappa____ phi______ frames
    -      -19.5262  -99.0000  -30.0000 30

  4 omega  -98.00  -56.00   1.2000   14.0000
omega____ theta____ kappa____ phi______ frames
    -      -19.5262  178.0000    0.0000 35

  5 omega  -44.00   78.40   1.2000   14.0000
omega____ theta____ kappa____ phi______ frames
    -       22.8075   19.0000  120.0000 102
;
_diffrn_measurement_device_type  'SuperNova, Dual, Cu at zero, Eos'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_UB_11      0.0090729000
_diffrn_orient_matrix_UB_12      -0.0048901000
_diffrn_orient_matrix_UB_13      -0.0313042000
_diffrn_orient_matrix_UB_21      -0.0107588000
_diffrn_orient_matrix_UB_22      -0.0293629000
_diffrn_orient_matrix_UB_23      -0.0012132000
_diffrn_orient_matrix_UB_31      -0.0197179000
_diffrn_orient_matrix_UB_32      0.0137715000
_diffrn_orient_matrix_UB_33      -0.0137272000
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0966
_diffrn_reflns_av_unetI/netI     0.0719
_diffrn_reflns_limit_h_max       33
_diffrn_reflns_limit_h_min       -34
_diffrn_reflns_limit_k_max       25
_diffrn_reflns_limit_k_min       -25
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            56649
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         3.02
_diffrn_source                   'SuperNova (Mo) X-ray Source'
_exptl_absorpt_coefficient_mu    0.084
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.38946
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro, Agilent Technologies,
Version 1.171.36.28 (release 01-02-2013 CrysAlis171 .NET)
(compiled Feb  1 2013,16:14:44)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            'clear light yellow'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   light
_exptl_crystal_colour_primary    yellow
_exptl_crystal_density_diffrn    1.085
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             4648
_exptl_crystal_size_max          0.34
_exptl_crystal_size_mid          0.32
_exptl_crystal_size_min          0.16
_refine_diff_density_max         1.017
_refine_diff_density_min         -0.411
_refine_diff_density_rms         0.072
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.097
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     734
_refine_ls_number_reflns         11485
_refine_ls_number_restraints     48
_refine_ls_restrained_S_all      1.095
_refine_ls_R_factor_all          0.1117
_refine_ls_R_factor_gt           0.0785
_refine_ls_shift/su_max          0.005
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1256P)^2^+2.5916P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2090
_refine_ls_wR_factor_ref         0.2374
_reflns_number_gt                7821
_reflns_number_total             11485
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c5dt01784j2.cif
_cod_data_source_block           sunyy1022
_cod_depositor_comments
'Adding full bibliography for 7036166--7036168.cif.'
_cod_original_formula_sum        'C67.50 H92 Mg2 N4 O4'
_cod_database_code               7036168
_reflns_odcompleteness_completeness 99.69
_reflns_odcompleteness_iscentric 1
_reflns_odcompleteness_theta     26.32
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2. Rigid bond restraints
 C66, C67, C68, C69, C70, C71
 with sigma for 1-2 distances of 0.001 and sigma for 1-3 distances of 0.001
3. Uiso/Uaniso restraints and constraints
C66 \\sim C67 \\sim C68 \\sim C69 \\sim C70 \\sim C71: within 1.7A with sigma
of 0.001 and sigma for terminal atoms of 0.002
4. Others
 Fixed Sof: H72A(0.5) H72B(0.5) H72C(0.5) C66(0.5) H66(0.5) C67(0.5) H67(0.5)
 C68(0.5) H68(0.5) C69(0.5) H69(0.5) C70(0.5) H70(0.5) C71(0.5) H71(0.5)
5.a Ternary CH refined with riding coordinates:
 C21(H21)
5.b Secondary CH2 refined with riding coordinates:
 C13(H13A,H13B), C12(H12A,H12B), C9(H9A,H9B), C10(H10A,H10B), C11(H11A,H11B),
 C8(H8A,H8B), C52(H52A,H52B)
5.c Aromatic/amide H refined with riding coordinates:
 C27(H27), C3(H3), C25(H25), C20(H20), C18(H18), C14(H14), C7(H7), C5(H5),
 C58(H58), C55(H55), C54(H54), C56(H56), C60(H60), C57(H57), C61(H61), C62(H62),
  C63(H63), C64(H64), C65(H65), C66(H66), C67(H67), C68(H68), C69(H69),
 C70(H70), C71(H71)
5.d Fitted hexagon refined as free rotating group:
 C66(C67,C68,C69,C70,C71)
5.e Idealised Me refined as rotating group:
 C50(H50A,H50B,H50C), C39(H39A,H39B,H39C), C47(H47A,H47B,H47C), C37(H37A,H37B,
 H37C), C38(H38A,H38B,H38C), C31(H31A,H31B,H31C), C41(H41A,H41B,H41C), C29(H29A,
 H29B,H29C), C46(H46A,H46B,H46C), C45(H45A,H45B,H45C), C30(H30A,H30B,H30C),
 C35(H35A,H35B,H35C), C34(H34A,H34B,H34C), C42(H42A,H42B,H42C), C43(H43A,H43B,
 H43C), C33(H33A,H33B,H33C), C49(H49A,H49B,H49C), C72(H72A,H72B,H72C), C51(H51A,
 H51B,H51C)
;
_olex2_submission_special_instructions 'No special instructions were received'