Disorder-Order Ferroelectric Transition in the Metal Formate Framework of [NH4][Zn(HCOO)3]
Guan-Cheng Xu; Xiao-Ming Ma; Li Zhang; Zhe-Ming Wang; Song Gao; Journal of the American Chemical Society 132 (2010) 9588–9590; doi:10.1021/ja104263m

data_4102682
_publ_section_title
;
 Disorder-Order Ferroelectric Transition in the Metal Formate Framework of
 [NH4][Zn(HCOO)3]
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              9588
_journal_page_last               9590
_journal_paper_doi               10.1021/ja104263m
_journal_volume                  132
_journal_year                    2010
_chemical_formula_sum            'C3 H7 N O6 Zn'
_chemical_formula_weight         218.47
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           182
_symmetry_cell_setting           hexagonal
_symmetry_space_group_name_Hall  'P 6c 2c'
_symmetry_space_group_name_H-M   'P 63 2 2'
_atom_sites_solution_hydrogens   difmap
_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            2
_cell_length_a                   7.3084(2)
_cell_length_b                   7.3084(2)
_cell_length_c                   8.1705(3)
_cell_measurement_reflns_used    2918
_cell_measurement_temperature    290(2)
_cell_measurement_theta_max      29.131
_cell_measurement_theta_min      3.395
_cell_volume                     377.94(2)
_computing_cell_refinement       'HKL Scalepack (Otwinowski & Minor, 1997)'
_computing_data_collection       'KappaCCD (Nonius B. V., 1998)'
_computing_data_reduction
'HKL Denzo (Otwinowski & Minor, 1997) & maXus (Mackay et al., 1998)'
_computing_molecular_graphics    'Bruker SHELXTL V5.1 (Sheldrick, 1998)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      290(2)
_diffrn_detector_area_resol_mean 9
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'NONIUS KappaCCD'
_diffrn_measurement_method       CCD
_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  0.0498
_diffrn_reflns_av_sigmaI/netI    0.0172
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            6989
_diffrn_reflns_theta_full        29.09
_diffrn_reflns_theta_max         29.09
_diffrn_reflns_theta_min         4.99
_exptl_absorpt_coefficient_mu    3.235
_exptl_absorpt_correction_T_max  0.446
_exptl_absorpt_correction_T_min  0.375
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
multi-scan from symmetry-related measurements 
 Sortav (Blessing 1995, 1997)
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.920
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'hexagonal block'
_exptl_crystal_F_000             220
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.26
_refine_diff_density_max         0.200
_refine_diff_density_min         -0.529
_refine_diff_density_rms         0.056
_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       1.03(5)
_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   1.080
_refine_ls_hydrogen_treatment    refined
_refine_ls_matrix_type           full
_refine_ls_number_parameters     26
_refine_ls_number_reflns         341
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.080
_refine_ls_R_factor_all          0.0220
_refine_ls_R_factor_gt           0.0191
_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^)+(0.0322P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0444
_refine_ls_wR_factor_ref         0.0453
_reflns_number_gt                316
_reflns_number_total             341
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja104263m_si_003.cif
_cod_data_source_block           1-at-290K
_cod_database_code               4102682