Ferroelastoelectric ordering in (NH4)2CuBr4·2H2O single crystal
Małuszyńska, Hanna; Tylczyński, Zbigniew; Cousson, Alain; CrystEngComm 15 (2013) 7498–; doi:10.1039/c3ce41113c

data_7214572
_publ_section_title
;
 Ferroelastoelectric ordering in (NH4)2CuBr4&#x00B7;2H2O single crystal
;
_journal_issue                   37
_journal_name_full               CrystEngComm
_journal_page_first              7498
_journal_paper_doi               10.1039/c3ce41113c
_journal_volume                  15
_journal_year                    2013
_chemical_formula_sum            'Br4 Cu H12 N2 O2'
_chemical_formula_weight         451.00
_chemical_name_systematic
; 
 diammonium tetrabromocuprate dihydrate   
;
_space_group_IT_number           136
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  '-P 4n 2n'
_symmetry_space_group_name_H-M   'P 42/m n m'
_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                90.00
_cell_formula_units_Z            2
_cell_length_a                   7.9940(11)
_cell_length_b                   7.9940(11)
_cell_length_c                   8.2750(17)
_cell_measurement_temperature    293(2)
_cell_volume                     528.81(15)
_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_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           neutron
_diffrn_radiation_wavelength     0.82920
_diffrn_reflns_av_R_equivalents  0.0596
_diffrn_reflns_av_sigmaI/netI    0.0522
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -2
_diffrn_reflns_number            1811
_diffrn_reflns_theta_full        35.47
_diffrn_reflns_theta_max         35.47
_diffrn_reflns_theta_min         3.54
_exptl_absorpt_coefficient_mu    0.000
_exptl_crystal_colour            green
_exptl_crystal_density_diffrn    2.832
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             41
_exptl_crystal_size_max          6
_exptl_crystal_size_mid          4
_exptl_crystal_size_min          3
_refine_diff_density_max         0.550
_refine_diff_density_min         -0.539
_refine_diff_density_rms         0.108
_refine_ls_extinction_coef       0.161(10)
_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   1.001
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     44
_refine_ls_number_reflns         688
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.001
_refine_ls_R_factor_all          0.0656
_refine_ls_R_factor_gt           0.0337
_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^)+(0.0415P)^2^+0.0424P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0760
_refine_ls_wR_factor_ref         0.0865
_reflns_number_gt                482
_reflns_number_total             688
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c3ce41113c.txt
_cod_data_source_block           p42mnm
_cod_original_sg_symbol_H-M      P42/mnm
_cod_database_code               7214572