High Molecular Weight Cyclic Polysiloxane from Organocatalytic Zwitterionic Polymerization of Constrained Spirocyclosiloxanes
Wu, Chunyan; Yu, Jianyi; li, qiaosheng; Liu, Yuzhou; Polymer Chemistry  (2017) –; doi:10.1039/C7PY01499F

data_1547945
_publ_section_title
;
 High Molecular Weight Cyclic Polysiloxane from Organocatalytic
 Zwitterionic Polymerization of Constrained Spirocyclosiloxanes
;
_journal_name_full               'Polymer Chemistry'
_journal_paper_doi               10.1039/C7PY01499F
_journal_year                    2017
_chemical_formula_sum            'C8 H24 O6 Si5'
_chemical_formula_weight         356.72
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2yn'
_space_group_name_H-M_alt        'P 1 21/n 1'
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_audit_block_doi                 10.5517/ccdc.csd.cc1mpn87
_audit_creation_method           SHELXL-2014/7
_audit_update_record
;
2016-10-18 deposited with the CCDC.
2017-11-06 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 113.174(6)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   10.043(5)
_cell_length_b                   18.838(9)
_cell_length_c                   11.150(5)
_cell_measurement_reflns_used    2090
_cell_measurement_temperature    200(2)
_cell_measurement_theta_max      19.52
_cell_measurement_theta_min      2.46
_cell_volume                     1939.3(16)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXT (Sheldrick 2014)'
_diffrn_ambient_temperature      200(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_unetI/netI     0.1237
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            13172
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        22.047
_diffrn_reflns_theta_max         22.047
_diffrn_reflns_theta_min         2.162
_exptl_absorpt_coefficient_mu    0.382
_exptl_absorpt_correction_T_max  0.861817
_exptl_absorpt_correction_T_min  0.737632
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   TWINABS
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.222
_exptl_crystal_description       needle
_exptl_crystal_F_000             760
_exptl_crystal_size_max          0.500
_exptl_crystal_size_mid          0.050
_exptl_crystal_size_min          0.050
_refine_diff_density_max         0.523
_refine_diff_density_min         -0.325
_refine_diff_density_rms         0.092
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.019
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     184
_refine_ls_number_reflns         13172
_refine_ls_number_restraints     12
_refine_ls_restrained_S_all      1.027
_refine_ls_R_factor_all          0.1533
_refine_ls_R_factor_gt           0.0823
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0995P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1789
_refine_ls_wR_factor_ref         0.2127
_reflns_Friedel_coverage         0.000
_reflns_number_gt                7398
_reflns_number_total             13172
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c7py01499f2.cif
_cod_data_source_block           16yzl2h_twin5
_cod_original_cell_volume        1939.3(15)
_cod_database_code               1547945
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.832
_shelx_estimated_absorpt_t_max   0.981
_shelx_res_checksum              96806