Bromocholine bromide is a molecular ferroelectric with moderate phase transition temperature
Wang, Sha-Sha; Chen, Xiao-Xian; Huang, Bo; Su, Yu-Jun; Zhang, Wei-Xiong; Zeng, Ming-Hua; Chen, Xiao-Ming; Journal of Materials Chemistry C 6 (2018) 2221–; doi:10.1039/C8TC00419F

data_7237286
_publ_section_title
;
 Bromocholine bromide is a molecular ferroelectric with moderate phase
 transition temperature
;
_journal_issue                   9
_journal_name_full               'Journal of Materials Chemistry C'
_journal_page_first              2221
_journal_paper_doi               10.1039/C8TC00419F
_journal_volume                  6
_journal_year                    2018
_chemical_formula_moiety         '0.5(C10 H26 Br2 N2), Br'
_chemical_formula_sum            'C5 H13 Br2 N'
_chemical_formula_weight         246.98
_chemical_name_common            'bromocholine bromide'
_chemical_name_systematic        '(2-Bromoethyl)trimethylammonium bromide '
_space_group_crystal_system      monoclinic
_space_group_IT_number           11
_space_group_name_Hall           '-P 2yb'
_space_group_name_H-M_alt        'P 1 21/m 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_audit_creation_date             2017-10-03
_audit_creation_method
;
Olex2 1.2
(compiled 2017.08.10 svn.r3458 for OlexSys, GUI svn.r5381)
;
_audit_update_record
;
2018-01-24 deposited with the CCDC.
2018-02-07 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 109.395(9)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   7.3865(6)
_cell_length_b                   8.6160(6)
_cell_length_c                   7.5120(6)
_cell_measurement_reflns_used    1521
_cell_measurement_temperature    353(2)
_cell_measurement_theta_max      28.1770
_cell_measurement_theta_min      2.8640
_cell_volume                     450.95(7)
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'ShelXL (Sheldrick, 2015)'
_computing_structure_solution    'XS (Sheldrick, 2008)'
_diffrn_ambient_temperature      353
_diffrn_measured_fraction_theta_full 0.975
_diffrn_measured_fraction_theta_max 0.975
_diffrn_measurement_device_type  'multiwire proportional'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0299
_diffrn_reflns_av_unetI/netI     0.0243
_diffrn_reflns_Laue_measured_fraction_full 0.975
_diffrn_reflns_Laue_measured_fraction_max 0.975
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            2838
_diffrn_reflns_point_group_measured_fraction_full 0.975
_diffrn_reflns_point_group_measured_fraction_max 0.975
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.997
_diffrn_reflns_theta_min         2.875
_exptl_absorpt_coefficient_mu    8.908
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.819
_exptl_crystal_description       block
_exptl_crystal_F_000             240
_exptl_crystal_recrystallization_method
'Re-crystallisation from solvent: methanol'
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.3
_exptl_crystal_size_min          0.3
_refine_diff_density_max         0.312
_refine_diff_density_min         -0.480
_refine_diff_density_rms         0.088
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.087
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     70
_refine_ls_number_reflns         921
_refine_ls_number_restraints     18
_refine_ls_restrained_S_all      1.121
_refine_ls_R_factor_all          0.0374
_refine_ls_R_factor_gt           0.0296
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0438P)^2^+0.0292P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0719
_refine_ls_wR_factor_ref         0.0748
_reflns_Friedel_coverage         0.000
_reflns_number_gt                771
_reflns_number_total             921
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c8tc00419f2.cif
_cod_data_source_block           HT
_cod_original_cell_volume        450.95(6)
_cod_database_code               7237286
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_max   0.175
_shelx_estimated_absorpt_t_min   0.175
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H,H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2. Restrained distances
 N1-C2 = N1-C3 = N1-C1 = N1-C4 = C4-C5
 1.5 with sigma of 0.01
 C2-C3 = C3-C1 = C1-C2 = C4-C2 = C4-C3 = C4-C1 = N1-C5
 2.48 with sigma of 0.02
3. Uiso/Uaniso restraints and constraints
Uanis(C3) \\sim Ueq: with sigma of 0.02 and sigma for terminal atoms of 0.02
4. Others
 Fixed Sof: C2(0.5) H2A(0.5) H2B(0.5) H2C(0.5) C3(0.5) H3A(0.5) H3B(0.5)
 H3C(0.5) C1(0.5) H1A(0.5) H1B(0.5) H1C(0.5) C4(0.5) H4A(0.5) H4B(0.5) C5(0.5)
 H5A(0.5) H5B(0.5) Br1(0.5)
5.a Secondary CH2 refined with riding coordinates:
 C4(H4A,H4B), C5(H5A,H5B)
5.b Idealised Me refined as rotating group:
 C2(H2A,H2B,H2C), C3(H3A,H3B,H3C), C1(H1A,H1B,H1C)
;
_shelx_res_checksum              86341
_shelx_hkl_checksum              46594
_olex2_submission_special_instructions 'No special instructions were received'