A spiro-type ammonium based switchable dielectric material with two sequential reversible phase transitions above room temperature
Wang, Xiao-Li; Zhou, Lin; Ye, Qiong; Geng, Fu-Juan; Ye, Heng-Yun; Fu, Da-Wei; Zhang, Yi; RSC Adv.  (2016) –; doi:10.1039/C6RA14157A

data_7226054
_publ_section_title
;
 A spiro-type ammonium based switchable dielectric material with two
 sequential reversible phase transitions above room temperature
;
_journal_name_full               'RSC Adv.'
_journal_paper_doi               10.1039/C6RA14157A
_journal_year                    2016
_chemical_formula_moiety         '2(C8 H16 N), Br4 Cd'
_chemical_formula_sum            'C16 H32 Br4 Cd N2'
_chemical_formula_weight         684.45
_chemical_name_systematic
; 
 ? 
;
_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
_audit_creation_method           SHELXL-97
_audit_update_record
;
2016-05-30 deposited with the CCDC.
2016-07-26 downloaded from the CCDC.
;
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   9.2978(19)
_cell_length_b                   18.028(4)
_cell_length_c                   14.049(3)
_cell_measurement_reflns_used    16182
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      27.48
_cell_measurement_theta_min      3.11
_cell_volume                     2354.9(9)
_computing_cell_refinement       'CrystalClear (Rigaku, 2005)'
_computing_data_collection       'CrystalClear (Rigaku, 2005)'
_computing_data_reduction        'CrystalClear (Rigaku, 2005)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Rigaku, SCXmini'
_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  0.1146
_diffrn_reflns_av_sigmaI/netI    0.1376
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -23
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            16182
_diffrn_reflns_theta_full        27.48
_diffrn_reflns_theta_max         27.48
_diffrn_reflns_theta_min         3.11
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  9
_exptl_absorpt_coefficient_mu    7.715
_exptl_absorpt_correction_T_max  0.3075
_exptl_absorpt_correction_T_min  0.3075
_exptl_absorpt_process_details   'CrystalClear (Rigaku, 2005)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.931
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1320
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.794
_refine_diff_density_min         -0.556
_refine_diff_density_rms         0.133
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.02(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.001
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     208
_refine_ls_number_reflns         5383
_refine_ls_number_restraints     85
_refine_ls_restrained_S_all      1.003
_refine_ls_R_factor_all          0.1835
_refine_ls_R_factor_gt           0.0742
_refine_ls_shift/su_max          0.094
_refine_ls_shift/su_mean         0.010
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0734P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1493
_refine_ls_wR_factor_ref         0.1883
_reflns_number_gt                2401
_reflns_number_total             5383
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c6ra14157a2.cif
_cod_data_source_block           2
_cod_original_cell_volume        2354.9(8)
_cod_database_code               7226054