New Ferroelectrics Based on Divalent Metal Ion Alum
Wen Zhang; Li-Zhuang Chen; Ren-Gen Xiong; Takayoshi Nakamura; Songping D. Huang; Journal of the American Chemical Society 131 (2009) 12544–12545; doi:10.1021/ja905399x

data_4104998
_publ_section_title
;
 New Ferroelectrics Based on Divalent Metal Ion Alum
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              12544
_journal_page_last               12545
_journal_paper_doi               10.1021/ja905399x
_journal_volume                  131
_journal_year                    2009
_chemical_formula_sum            'C6 H26 Cu N2 O14 Se2'
_chemical_formula_weight         571.75
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 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                 91.730(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   7.1471(5)
_cell_length_b                   12.6152(8)
_cell_length_c                   9.9519(7)
_cell_measurement_temperature    103(2)
_cell_volume                     896.88(11)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      103(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71075
_diffrn_reflns_av_R_equivalents  0.0428
_diffrn_reflns_av_sigmaI/netI    0.0618
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            8751
_diffrn_reflns_theta_full        27.43
_diffrn_reflns_theta_max         27.43
_diffrn_reflns_theta_min         3.23
_exptl_absorpt_coefficient_mu    5.347
_exptl_absorpt_correction_T_max  1.0000
_exptl_absorpt_correction_T_min  0.8995
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_density_diffrn    2.117
_exptl_crystal_F_000             570
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.30
_refine_diff_density_max         0.896
_refine_diff_density_min         -0.551
_refine_diff_density_rms         0.102
_refine_ls_abs_structure_details
'Flack H D (1983), Acta Cryst. A39, 876-881 base on 1941 Friedel pairs'
_refine_ls_abs_structure_Flack   0.514(9)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.063
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     228
_refine_ls_number_reflns         4077
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.063
_refine_ls_R_factor_all          0.0289
_refine_ls_R_factor_gt           0.0281
_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^)+(0.0098P)^2^+0.6077P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0642
_refine_ls_wR_factor_ref         0.0648
_reflns_number_gt                3973
_reflns_number_total             4077
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja905399x_si_001.cif
_cod_data_source_block           shelxs
_cod_database_code               4104998