1,1',2,2'-Tetramethyl-3,3'-(<i>p</i>-phenylenedimethylene)diimidazol-1-ium dibromide
Puvaneswary, Subramaniam; Alias, Yatimah; Ng, Seik Weng; Acta Crystallographica Section E 65 (2009) o1828–; doi:10.1107/S1600536809026324

data_2222895
_publ_section_title
;
 1,1',2,2'-Tetramethyl-3,3'-(<i>p</i>-phenylenedimethylene)diimidazol-1-ium
 dibromide
;
_journal_coeditor_code           TK2494
_journal_issue                   8
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o1828
_journal_paper_doi               10.1107/S1600536809026324
_journal_volume                  65
_journal_year                    2009
_chemical_formula_iupac          'C18 H24 N4 2+, 2Br -'
_chemical_formula_moiety         'C18 H24 N4 2+, 2(Br -)'
_chemical_formula_sum            'C18 H24 Br2 N4'
_chemical_formula_weight         456.23
_chemical_name_systematic
;
1,1',2,2'-Tetramethyl-3,3'-(<i>p</i>-phenylenedimethylene)diimidazol-1-ium
dibromide
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90
_cell_angle_beta                 93.222(3)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   8.5689(4)
_cell_length_b                   9.8617(5)
_cell_length_c                   11.0272(4)
_cell_measurement_reflns_used    1543
_cell_measurement_temperature    140(2)
_cell_measurement_theta_max      25.5
_cell_measurement_theta_min      2.8
_cell_volume                     930.37(7)
_computing_cell_refinement       'SAINT (Bruker, 2008)'
_computing_data_collection       'APEX2 (Bruker, 2008)'
_computing_data_reduction        'SAINT (Bruker, 2008)'
_computing_molecular_graphics    'X-SEED (Barbour, 2001)'
_computing_publication_material  'publCIF (Westrip, 2009)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      140(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker SMART APEX'
_diffrn_measurement_method       \w
_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  0.051
_diffrn_reflns_av_sigmaI/netI    0.067
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            5882
_diffrn_reflns_theta_full        27.5
_diffrn_reflns_theta_max         27.5
_diffrn_reflns_theta_min         2.8
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    4.364
_exptl_absorpt_correction_T_max  0.845
_exptl_absorpt_correction_T_min  0.274
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 1996)'
_exptl_crystal_colour            Colorless
_exptl_crystal_density_diffrn    1.629
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Prism
_exptl_crystal_F_000             460
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.08
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.54
_refine_diff_density_min         -0.99
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.04
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     112
_refine_ls_number_reflns         2131
_refine_ls_number_restraints     36
_refine_ls_restrained_S_all      1.04
_refine_ls_R_factor_all          0.065
_refine_ls_R_factor_gt           0.039
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0403P)^2^+0.5004P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.087
_refine_ls_wR_factor_ref         0.096
_reflns_number_gt                1575
_reflns_number_total             2131
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            tk2494.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from
2010-06-29.

'_exptl_absorpt_correction_type' value 'Multi-scan' changed
to 'multi-scan' according to
'/home/saulius/struct/CIF-dictionaries/cif_core.dic' dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from
2010-06-29.

'_exptl_absorpt_correction_type' value 'Multi-scan'
changed to 'multi-scan' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               2222895
_cod_database_fobs_code          2222895