Structure of a Benzylcalcium Diastereomer: An Initiator for the Anionic Polymerization of Styrene
Harder, Sjoerd; Feil, Florian; Weeber, Armin; Organometallics 20 (2001) 1044–; doi:10.1021/om000945p

data_4077254
_publ_section_title
;
 Structure of a Benzylcalcium Diastereomer:&#x00A0; An Initiator for the
 Anionic Polymerization of Styrene
;
_journal_issue                   6
_journal_name_full               Organometallics
_journal_page_first              1044
_journal_paper_doi               10.1021/om000945p
_journal_volume                  20
_journal_year                    2001
_chemical_formula_sum            'C32 H56 Ca N2 O2 Si2'
_chemical_formula_weight         597.05
_chemical_name_systematic
; 
 ? 
;
_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                 107.515(5)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   16.302(2)
_cell_length_b                   12.761(2)
_cell_length_c                   17.772(2)
_cell_measurement_temperature    293(2)
_cell_volume                     3525.7(8)
_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_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  0.0358
_diffrn_reflns_av_sigmaI/netI    0.0431
_diffrn_reflns_limit_h_max       19
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            6406
_diffrn_reflns_theta_full        24.97
_diffrn_reflns_theta_max         24.97
_diffrn_reflns_theta_min         1.31
_exptl_absorpt_coefficient_mu    0.274
_exptl_crystal_colour            light-yellow
_exptl_crystal_density_diffrn    1.125
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             1304
_refine_diff_density_max         0.427
_refine_diff_density_min         -0.404
_refine_diff_density_rms         0.048
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.029
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     570
_refine_ls_number_reflns         6174
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.029
_refine_ls_R_factor_all          0.0765
_refine_ls_R_factor_gt           0.0393
_refine_ls_shift/su_max          0.176
_refine_ls_shift/su_mean         0.003
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0439P)^2^+2.1079P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0907
_refine_ls_wR_factor_ref         0.1033
_reflns_number_gt                4445
_reflns_number_total             6174
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            om000945p.cif
_cod_data_source_block           (dmat)2Ca.(THF)2
_cod_original_sg_symbol_H-M      P21/c
_cod_database_code               4077254