A 3D chiral Zn(II) coordination polymer with triple Zn-oba-Zn helical chains (oba = 4,4'-oxybis(benzoate)).
Ma, Yi; Han, Zhengbo; He, Yongke; Yang, Liguo; Chemical communications (Cambridge, England)  (2007) 4107–4109; doi:10.1039/b708479j

data_7102194
_publ_section_title
;
 A 3D chiral Zn(II) coordination polymer with triple Zn-oba-Zn helical
 chains (oba = 4,4'-oxybis(benzoate)).
;
_journal_issue                   40
_journal_name_full
'Chemical communications (Cambridge, England)'
_journal_page_first              4107
_journal_page_last               4109
_journal_paper_doi               10.1039/b708479j
_journal_year                    2007
_chemical_formula_sum            'C28 H16 N0 O10 Zn2'
_chemical_formula_weight         643.15
_chemical_name_systematic
;
?
;
_space_group_IT_number           154
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_Hall  'P 32 2"'
_symmetry_space_group_name_H-M   'P 32 2 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                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            6
_cell_length_a                   13.298(2)
_cell_length_b                   13.298(2)
_cell_length_c                   29.544(5)
_cell_measurement_temperature    293(2)
_cell_volume                     4524.5(12)
_computing_cell_refinement       'XSCANS (Siemens, 1994)'
_computing_data_collection       'XSCANS (Siemens, 1994)'
_computing_data_reduction        'XSCANS (Siemens, 1994)'
_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 P4'
_diffrn_measurement_method       '\w 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  0.0361
_diffrn_reflns_av_sigmaI/netI    0.0649
_diffrn_reflns_limit_h_max       1
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -1
_diffrn_reflns_limit_l_max       38
_diffrn_reflns_limit_l_min       -1
_diffrn_reflns_number            8644
_diffrn_reflns_theta_full        27.49
_diffrn_reflns_theta_max         27.49
_diffrn_reflns_theta_min         1.77
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 97
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    1.641
_exptl_absorpt_correction_T_max  0.6656
_exptl_absorpt_correction_T_min  0.5189
_exptl_absorpt_correction_type   psi-scan
_exptl_crystal_colour            Colorless
_exptl_crystal_density_diffrn    1.416
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Block
_exptl_crystal_F_000             1944
_exptl_crystal_size_max          0.46
_exptl_crystal_size_mid          0.35
_exptl_crystal_size_min          0.27
_refine_diff_density_max         1.619
_refine_diff_density_min         -0.799
_refine_diff_density_rms         0.251
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.01(3)
_refine_ls_extinction_coef       0.0132(12)
_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   1.041
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     362
_refine_ls_number_reflns         6834
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.041
_refine_ls_R_factor_all          0.1153
_refine_ls_R_factor_gt           0.0738
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1362P)^2^+4.4498P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1936
_refine_ls_wR_factor_ref         0.2357
_reflns_number_gt                4658
_reflns_number_total             6834
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b708479j.txt
_cod_data_source_block           1
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Trigonal' changed to 'trigonal' 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_enum 1527 2010-12-29 10:47:43Z saulius 
;
_cod_original_sg_symbol_H-M      P3(2)21
_cod_database_code               7102194