Above Room Temperature Organic Ferroelectrics: Diprotonated 1,4-Diazabicyclo[2.2.2]octane Shifts between Two 2-Chlorobenzoates.
Yao, Zi-Shuo; Yamamoto, Kaoru; Cai, Hong-Ling; Takahashi, Kazuyuki; Sato, Osamu; Journal of the American Chemical Society 138 (2016) 12005–12008; doi:10.1021/jacs.6b03747

data_4125230
_publ_section_title
;
 Above Room Temperature Organic Ferroelectrics: Diprotonated
 1,4-Diazabicyclo[2.2.2]octane Shifts between Two 2-Chlorobenzoates.
;
_journal_issue                   37
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              12005
_journal_page_last               12008
_journal_paper_doi               10.1021/jacs.6b03747
_journal_volume                  138
_journal_year                    2016
_chemical_formula_sum            'C20 H22 Cl2 N2 O4'
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_space_group_name_H-M_alt        'P c a 21'
_symmetry_space_group_name_Hall  'P 2c -2ac'
_symmetry_space_group_name_H-M   'P c a 21'
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_cell_angle_gamma                90
_cell_formula_units_Z            4
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_cell_measurement_temperature    293(2)
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_cell_volume                     2012.7(16)
_computing_cell_refinement       'CrystalClear (Rigaku Inc., 2008)'
_computing_data_collection       'CrystalClear (Rigaku Inc., 2008)'
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_computing_structure_solution    'sir 2008'
_diffrn_ambient_temperature      293(2)
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_diffrn_measurement_device_type  Molybdenum
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_diffrn_radiation_type           MoK\a
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_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       14
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_diffrn_reflns_theta_full        25.242
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_diffrn_reflns_theta_min         3.072
_diffrn_source                   'Rotating Anode'
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_exptl_absorpt_correction_T_max  1.0000
_exptl_absorpt_correction_T_min  0.7198
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            Colorless
_exptl_crystal_density_diffrn    1.403
_exptl_crystal_description       Prism
_exptl_crystal_F_000             888
_exptl_crystal_size_max          0.170
_exptl_crystal_size_mid          0.140
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_refine_ls_abs_structure_details
;
 Flack x determined using 585 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons and Flack (2004), Acta Cryst. A60, s61).
;
_refine_ls_abs_structure_Flack   0.03(4)
_refine_ls_extinction_method     none
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_refine_ls_restrained_S_all      0.942
_refine_ls_R_factor_all          0.0485
_refine_ls_R_factor_gt           0.0430
_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^)+(0.1000P)^2^+0.2000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1248
_refine_ls_wR_factor_ref         0.1336
_reflns_Friedel_coverage         0.379
_reflns_Friedel_fraction_full    0.426
_reflns_Friedel_fraction_max     0.424
_reflns_number_gt                2539
_reflns_number_total             2829
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja6b03747_si_003.cif
_cod_data_source_block           shelx
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_absorpt_correction_type' value 'Multi-scan' changed to
'multi-scan' according to
/usr/data/users/saulius/crontab/automatic-downloads/rss-feeds/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 4268 2015-11-12 08:31:59Z antanas 

 Adding full bibliography for 4125230--4125234.cif.
;
_cod_original_cell_volume        2012.7(15)
_cod_database_code               4125230
_shelx_estimated_absorpt_t_min   0.943
_shelx_estimated_absorpt_t_max   0.976
_shelxl_version_number           2013-4