Remarkable effect of alkali metal on polymerization of cyclic esters catalyzed by samarium-alkali metal multinuclear alkoxide clusters.
Sheng, Hongting; Shi, Jianhua; Feng, Yan; Wang, Hui; Jiao, Yonghua; Sheng, Hanjing; Zhang, Yong; Shen, Qi; Dalton transactions (Cambridge, England : 2003) 41 (2012) 9232–9240; doi:10.1039/c2dt30677h

data_7019816
_publ_section_title
;
 Remarkable effect of alkali metal on polymerization of cyclic esters
 catalyzed by samarium-alkali metal multinuclear alkoxide clusters.
;
_journal_issue                   30
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              9232
_journal_page_last               9240
_journal_paper_doi               10.1039/c2dt30677h
_journal_volume                  41
_journal_year                    2012
_chemical_formula_moiety         'C104 H266 K20 N26 O32 Sm4, C7 H8'
_chemical_formula_sum            'C111 H274 K20 N26 O32 Sm4'
_chemical_formula_weight         3868.96
_chemical_name_systematic
;
?
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      14
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 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                 105.199(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   22.9002(16)
_cell_length_b                   15.9730(10)
_cell_length_c                   25.9698(18)
_cell_measurement_reflns_used    31084
_cell_measurement_temperature    153(2)
_cell_measurement_theta_max      25.3
_cell_measurement_theta_min      3.0
_cell_volume                     9167.1(11)
_computing_cell_refinement       CrystalClear
_computing_data_collection       CrystalClear
_computing_data_reduction        CrystalStructure
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      153(2)
_diffrn_detector_area_resol_mean 7.31
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Rigaku Mercury'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71070
_diffrn_reflns_av_R_equivalents  0.0565
_diffrn_reflns_av_sigmaI/netI    0.0475
_diffrn_reflns_limit_h_max       27
_diffrn_reflns_limit_h_min       -27
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       30
_diffrn_reflns_limit_l_min       -31
_diffrn_reflns_number            88895
_diffrn_reflns_theta_full        25.35
_diffrn_reflns_theta_max         25.35
_diffrn_reflns_theta_min         3.02
_exptl_absorpt_coefficient_mu    1.780
_exptl_absorpt_correction_T_max  0.738
_exptl_absorpt_correction_T_min  0.490
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Jacobson, R. (1998) Private communication'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.402
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             4012
_exptl_crystal_size_max          0.45
_exptl_crystal_size_mid          0.38
_exptl_crystal_size_min          0.17
_refine_diff_density_max         1.421
_refine_diff_density_min         -1.334
_refine_diff_density_rms         0.119
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.125
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     914
_refine_ls_number_reflns         16759
_refine_ls_number_restraints     19
_refine_ls_restrained_S_all      1.127
_refine_ls_R_factor_all          0.0704
_refine_ls_R_factor_gt           0.0569
_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^)+(0.0416P)^2^+37.3174P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1189
_refine_ls_wR_factor_ref         0.1261
_reflns_number_gt                14232
_reflns_number_total             16759
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c2dt30677h.txt
_cod_data_source_block           complex1
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               7019816