Synthesis, Structure, and Catalytic Studies of Mixed Lithium−Magnesium and Sodium−Magnesium Complexes: Highly Isospecific Initiators for Polymerization of Methyl Methacrylate
Hsueh, Mao-Lin; Ko, Bao-Tsan; Athar, Taimur; Lin, Chu-Chieh; Wu, Tzong-Ming; Hsu, Sung-Fu; Organometallics 25 (2006) 4144–; doi:10.1021/om0603363

data_4075515
_publ_section_title
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 Synthesis, Structure, and Catalytic Studies of Mixed
 Lithium&#x2212;Magnesium and Sodium&#x2212;Magnesium Complexes:&#x00A0;
 Highly Isospecific Initiators for Polymerization of Methyl Methacrylate
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_journal_issue                   17
_journal_name_full               Organometallics
_journal_page_first              4144
_journal_paper_doi               10.1021/om0603363
_journal_volume                  25
_journal_year                    2006
_chemical_formula_sum            'C38 H63 Mg Na O3'
_chemical_formula_weight         615.18
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           56
_symmetry_cell_setting           orthorhombic
_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     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            8
_cell_length_a                   20.7678(12)
_cell_length_b                   21.2375(11)
_cell_length_c                   18.4101(11)
_cell_measurement_reflns_used    5362
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      21.684
_cell_measurement_theta_min      2.213
_cell_volume                     8119.9(8)
_computing_cell_refinement       'Bruker SAINT (Siemens, 1996)'
_computing_data_collection       'Bruker SMART (Siemens 1996)'
_computing_data_reduction        'Bruker SAINT'
_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 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker SMART 1000 CCD'
_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  0.0835
_diffrn_reflns_av_sigmaI/netI    0.0650
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -25
_diffrn_reflns_limit_k_max       26
_diffrn_reflns_limit_k_min       -22
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            43975
_diffrn_reflns_theta_full        26.02
_diffrn_reflns_theta_max         26.02
_diffrn_reflns_theta_min         1.37
_exptl_absorpt_coefficient_mu    0.084
_exptl_absorpt_correction_T_max  1.000
_exptl_absorpt_correction_T_min  0.625
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS, Sheldrick (1996)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.006
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       parallelpied
_exptl_crystal_F_000             2704
_exptl_crystal_size_max          0.62
_exptl_crystal_size_mid          0.58
_exptl_crystal_size_min          0.55
_refine_diff_density_max         0.323
_refine_diff_density_min         -0.222
_refine_diff_density_rms         0.047
_refine_ls_extinction_coef       0.0008(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.013
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     398
_refine_ls_number_reflns         7997
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.013
_refine_ls_R_factor_all          0.1418
_refine_ls_R_factor_gt           0.0648
_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^)+(0.1000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1723
_refine_ls_wR_factor_ref         0.2054
_reflns_number_gt                3625
_reflns_number_total             7997
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            om0603363si20060602_051112.cif
_cod_data_source_block           sasm01m
_cod_depositor_comments
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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 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      Pccn
_cod_database_code               4075515