Highly 3,4-Selective Living Polymerization of Isoprene with Rare Earth Metal Fluorenyl N-Heterocyclic Carbene Precursors
Wang, Baoli; Cui, Dongmei; Lv, Kui; Macromolecules 41 (2008) 1983–; doi:10.1021/ma702505n

data_1504420
_publ_section_title
;
 Highly 3,4-Selective Living Polymerization of Isoprene with Rare Earth
 Metal Fluorenyl N-Heterocyclic Carbene Precursors
;
_journal_issue                   6
_journal_name_full               Macromolecules
_journal_page_first              1983
_journal_paper_doi               10.1021/ma702505n
_journal_volume                  41
_journal_year                    2008
_chemical_formula_sum            'C31 H45 Ho N2 Si2'
_chemical_formula_weight         666.80
_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                 107.1900(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   10.5662(7)
_cell_length_b                   23.2337(14)
_cell_length_c                   13.8856(9)
_cell_measurement_temperature    187(2)
_cell_volume                     3256.5(4)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      187(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_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  0.0158
_diffrn_reflns_av_sigmaI/netI    0.0167
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       28
_diffrn_reflns_limit_k_min       -26
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            18080
_diffrn_reflns_theta_full        26.01
_diffrn_reflns_theta_max         26.01
_diffrn_reflns_theta_min         1.75
_exptl_absorpt_coefficient_mu    2.523
_exptl_absorpt_correction_T_max  0.6608
_exptl_absorpt_correction_T_min  0.4086
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    1.360
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1360
_exptl_crystal_size_max          0.43
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.18
_refine_diff_density_max         0.659
_refine_diff_density_min         -0.703
_refine_diff_density_rms         0.060
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.043
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     334
_refine_ls_number_reflns         6397
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.043
_refine_ls_R_factor_all          0.0240
_refine_ls_R_factor_gt           0.0215
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0259P)^2^+1.9175P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0519
_refine_ls_wR_factor_ref         0.0531
_reflns_number_gt                5884
_reflns_number_total             6397
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ma702505n-file001.cif
_cod_data_source_block           r154m
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
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      P2(1)/c
_cod_database_code               1504420