Hydrogen-Bonded Trimers in 4,4'-Dimethylbiphenyl-2,2'-dicarboxylic Acid
Gerkin, Roger E.; Acta Crystallographica Section C 54 (1998) 1887–1889; doi:10.1107/S0108270198009597

data_2007944
_publ_section_title
;
 Hydrogen-Bonded Trimers in 4,4'-Dimethylbiphenyl-2,2'-dicarboxylic
 Acid
;
_journal_issue                   12
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              1887
_journal_page_last               1889
_journal_paper_doi               10.1107/S0108270198009597
_journal_volume                  54
_journal_year                    1998
_chemical_formula_moiety         'C16 H14 O4 '
_chemical_formula_sum            'C16 H14 O4'
_chemical_formula_weight         270.28
_chemical_name_common            '4,4'-dimethylbiphenyl-2,2'-dicarboxylic acid'
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_cell_angle_alpha                90
_cell_angle_beta                 103.739(6)
_cell_angle_gamma                90
_cell_formula_units_Z            12
_cell_length_a                   18.955(2)
_cell_length_b                   12.1430(10)
_cell_length_c                   18.773(2)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    296
_cell_measurement_theta_max      17.2
_cell_measurement_theta_min      13.4
_cell_volume                     4197.4(7)
_computing_cell_refinement       'MSC/AFC Diffractometer Control Software'
_computing_data_collection
;MSC/AFC Diffractometer Control Software (Molecular Structure Corporation,
 1988)
;
_computing_data_reduction
'TEXSAN (Molecular Structure Corporation, 1995)'
_computing_molecular_graphics    'ORTEPII (Johnson, 1976)'
_computing_publication_material  'TEXSAN, PLATON (Spek, 1990)'
_computing_structure_refinement  TEXSAN
_computing_structure_solution    'SHELXS86 (Sheldrick, 1985)'
_diffrn_ambient_temperature      296
_diffrn_measurement_device_type  AFC5S
_diffrn_measurement_method       '\w scans '
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'X-ray tube'
_diffrn_radiation_type           MoK\a
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_diffrn_reflns_av_R_equivalents  0.023
_diffrn_reflns_limit_h_max       24
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       0
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_diffrn_reflns_limit_l_min       -24
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_diffrn_reflns_theta_max         27.56
_diffrn_reflns_theta_min         2.0
_diffrn_standards_decay_%        ' +-3.6% (average maximum relative intensity)'
_diffrn_standards_interval_count 150
_diffrn_standards_number         6
_exptl_absorpt_coefficient_mu    0.086
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.283
_exptl_crystal_density_meas      ?
_exptl_crystal_description       'cut rod'
_exptl_crystal_F_000             1704
_exptl_crystal_size_max          0.42
_exptl_crystal_size_mid          0.38
_exptl_crystal_size_min          0.31
_refine_diff_density_max         0.45
_refine_diff_density_min         -0.39
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_obs   1.79
_refine_ls_hydrogen_treatment
'H atoms treated by a mixture of independent and constrained refinement'
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_refine_ls_number_reflns         4850
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_refine_ls_shift/su_max          <0.01
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details     'w = 1/\s^2^(F^2^)'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_obs         0.094
_reflns_number_gt                2841
_reflns_number_total             4852
_reflns_threshold_expression     'I > 2.0\s(I)'
_cod_data_source_file            fr1147.cif
_cod_data_source_block           1
_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.

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

The following automatic conversions were performed:

'_atom_site_adp_type' tag value 'Uij' was replaced with 'Uani' value
30 times.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 

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.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'none' was changed to '?' - the
value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value '1/\s^2^(F^2^)' was changed to
'calc'. New tag '_refine_ls_weighting_details' was created. The value
of the new tag was set to 'w = 1/\s^2^(F^2^)'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_cell_volume        4197.3(6)
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               2007944