Symmetry constraints, molecular recognition and crystal engineering. Comparative structural studies of urea–butanedioic and urea–<i>E</i>-butanedioic acid (2:1) cocrystals
Videnova-Adrabińska, V.; Acta Crystallographica Section B 52 (1996) 1048–1056; doi:10.1107/S0108768196005216

data_2101616
_publ_section_title
;
 Symmetry constraints, molecular recognition and crystal engineering.
 Comparative structural studies of urea--butanedioic and
 urea--<i>E</i>-butanedioic acid (2:1) cocrystals
;
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              1048
_journal_page_last               1056
_journal_paper_doi               10.1107/S0108768196005216
_journal_volume                  52
_journal_year                    1996
_chemical_formula_sum            'C6 H14 N4 O6'
_chemical_formula_weight         238.20
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_type_scat_source           'Cromer & Waber (1974)'
_cell_angle_alpha                90.0
_cell_angle_beta                 96.80(5)
_cell_angle_gamma                90.0
_cell_formula_units_Z            2
_cell_length_a                   5.637(4)
_cell_length_b                   8.243(3)
_cell_length_c                   12.258(3)
_cell_measurement_reflns_used    48
_cell_measurement_temperature    297
_cell_measurement_theta_max      22.35
_cell_measurement_theta_min      10.05
_cell_volume                     565.6(5)
_diffrn_measurement_device       'Enraf-Nonius CAD-4'
_diffrn_measurement_method       \w-2\q
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.035
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            2364
_diffrn_reflns_theta_max         25.95
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  60
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.116
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.399
_exptl_crystal_description       prism
_exptl_crystal_F_000             252
_exptl_crystal_size_max          0.60
_exptl_crystal_size_mid          0.50
_exptl_crystal_size_min          0.40
_refine_diff_density_max         0.42
_refine_diff_density_min         -0.41
_refine_ls_extinction_coef       0.27511E-3
_refine_ls_extinction_method
'TEXSAN (Molecular Structure Corporation, 1985)'
_refine_ls_goodness_of_fit_obs   1.75
_refine_ls_hydrogen_treatment    'See text'
_refine_ls_number_parameters     94
_refine_ls_number_reflns         817
_refine_ls_R_factor_obs          0.057
_refine_ls_shift/esd_max         0.001
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details     'w = 4F~o~^2^/\s^2^(F~o~^2^)'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_obs         0.069
_reflns_number_observed          817
_reflns_number_total             1187
_reflns_observed_criterion       I>2\s(I)
_cod_data_source_file            ab0345.cif
_cod_data_source_block           ab0345a
_cod_depositor_comments
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The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'w = 4F~o~^2^/\s^2^(F~o~^2^)' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to 'w =
4F~o~^2^/\s^2^(F~o~^2^)'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
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_cod_original_cell_volume        565.6(8)
_cod_database_code               2101616