A study of zinc(II) coordination polymers with identical meso-helix based on 1,4-bis(2-methyl-imidazol-1-yl)butane
Rui-Li Zhao; Ke-Fen Yue; Chun-sheng Zhou; Qiao-De-Mei Cheng; Jing-Tao Shi; Yong-Liang Liu; Yao-Yu Wang; Inorganica Chimica Acta 402 (2013) 25–32; doi:

data_1517043
_publ_section_title
;
 A study of zinc(II) coordination polymers with identical meso-helix based
 on 1,4-bis(2-methyl-imidazol-1-yl)butane
;
_journal_name_full
;
Inorganica Chimica Acta
;
_journal_page_first              25
_journal_page_last               32
_journal_volume                  402
_journal_year                    2013
_chemical_formula_sum            'C24 H24 N6 O6 Zn'
_chemical_formula_weight         557.86
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.7076(14)
_cell_length_b                   15.686(3)
_cell_length_c                   19.368(3)
_cell_measurement_reflns_used    1875
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      19.18
_cell_measurement_theta_min      2.47
_cell_volume                     2645.4(8)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \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  0.0612
_diffrn_reflns_av_sigmaI/netI    0.0807
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            13387
_diffrn_reflns_theta_full        25.09
_diffrn_reflns_theta_max         25.09
_diffrn_reflns_theta_min         1.67
_exptl_absorpt_coefficient_mu    0.977
_exptl_absorpt_correction_T_max  0.8851
_exptl_absorpt_correction_T_min  0.7444
_exptl_absorpt_correction_type   none
_exptl_crystal_density_diffrn    1.401
_exptl_crystal_density_meas      0
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             1152
_exptl_crystal_size_max          0.32
_exptl_crystal_size_mid          0.26
_exptl_crystal_size_min          0.13
_refine_diff_density_max         0.874
_refine_diff_density_min         -0.498
_refine_diff_density_rms         0.115
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.02(3)
_refine_ls_extinction_coef       0.0035(11)
_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   1.033
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     327
_refine_ls_number_reflns         4710
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.033
_refine_ls_R_factor_all          0.0857
_refine_ls_R_factor_gt           0.0646
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1200P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1730
_refine_ls_wR_factor_ref         0.1975
_reflns_number_gt                3515
_reflns_number_total             4710
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ICA-2013-402-25-32-4.cif
_cod_data_source_block           xb3360_0m
_cod_original_cell_volume        2645.4(7)
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               1517043