From unexpected reactions to a new family of ionic co-crystals: the case of barbituric acid with alkali bromides and caesium iodide.
Braga, Dario; Grepioni, Fabrizia; Maini, Lucia; Prosperi, Susanna; Gobetto, Roberto; Chierotti, Michele R.; Chemical communications (Cambridge, England) 46 (2010) 7715–7717; doi:10.1039/c0cc02701d

data_7112885
_publ_section_title
;
 From unexpected reactions to a new family of ionic co-crystals: the case
 of barbituric acid with alkali bromides and caesium iodide.
;
_journal_issue                   41
_journal_name_full
'Chemical communications (Cambridge, England)'
_journal_page_first              7715
_journal_page_last               7717
_journal_paper_doi               10.1039/c0cc02701d
_journal_volume                  46
_journal_year                    2010
_chemical_formula_sum            'C4 H4 Br N2 O3 Rb'
_chemical_formula_weight         293.47
_chemical_name_systematic
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?
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_space_group_IT_number           14
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_cell_angle_alpha                90.00
_cell_angle_beta                 92.949(5)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.984(5)
_cell_length_b                   8.756(5)
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_cell_measurement_reflns_used    1644
_cell_measurement_temperature    293(2)
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_computing_cell_refinement
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CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.34d (release 27-02-2009 CrysAlis171 .NET)
(compiled Feb 27 2009,15:38:38)
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_computing_data_collection
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CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.34d (release 27-02-2009 CrysAlis171 .NET)
(compiled Feb 27 2009,15:38:38)
;
_computing_data_reduction
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CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.34d (release 27-02-2009 CrysAlis171 .NET)
(compiled Feb 27 2009,15:38:38)
;
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean 16.1340
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.834
_diffrn_measurement_device_type
'Goniometer KM4/Xcalibur, detector: Sapphire3'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enhance (Mo) X-ray Source'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0539
_diffrn_reflns_av_sigmaI/netI    0.0879
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       11
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_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            3512
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         29.30
_diffrn_reflns_theta_min         2.94
_exptl_absorpt_coefficient_mu    11.021
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.26022
_exptl_absorpt_correction_type   multi-scan
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CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.34d (release 27-02-2009 CrysAlis171 .NET)
(compiled Feb 27 2009,15:38:38)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
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_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    2.410
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Prism
_exptl_crystal_F_000             552
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.18
_exptl_crystal_size_min          0.16
_refine_diff_density_max         1.358
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_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.933
_refine_ls_hydrogen_treatment    mixed
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_refine_ls_number_parameters     108
_refine_ls_number_reflns         1843
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.933
_refine_ls_R_factor_all          0.0873
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_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0688P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1159
_refine_ls_wR_factor_ref         0.1247
_reflns_number_gt                1198
_reflns_number_total             1843
_reflns_threshold_expression     >2\s(I)
_cod_data_source_file            c0cc02701d.txt
_cod_data_source_block           acbarb_rbbr_d_raccolta
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to
/usr/data/users/saulius/automatic-downloads/retrospective/RSC/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 2281 2013-09-26 08:29:07Z andrius 
;
_cod_original_sg_symbol_H-M      P21/n
_cod_database_code               7112885