Co-crystals of caffeine and piracetam with 4-hydroxybenzoic acid: Unravelling the hidden hydrates of 1 : 1 co-crystals
Aitipamula, Srinivasulu; Chow, Pui Shan; Tan, Reginald B. H.; CrystEngComm 14 (2012) 2381–; doi:10.1039/c2ce25080b

data_7207675
_publ_section_title
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 Co-crystals of caffeine and piracetam with 4-hydroxybenzoic acid:
 Unravelling the hidden hydrates of 1&#x2009;:&#x2009;1 co-crystals
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_journal_issue                   7
_journal_name_full               CrystEngComm
_journal_page_first              2381
_journal_paper_doi               10.1039/c2ce25080b
_journal_volume                  14
_journal_year                    2012
_chemical_formula_sum            'C13 H18 N2 O6'
_chemical_formula_weight         298.29
_chemical_name_common
;
Monohydrate of Piracetam-4-hydroxybenzoic acid (1:1)
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_chemical_name_systematic
;
Monohydrate of Piracetam-4-hydroxybenzoic acid (1:1)
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                96.20(3)
_cell_angle_beta                 96.76(3)
_cell_angle_gamma                90.86(3)
_cell_formula_units_Z            2
_cell_length_a                   6.4211(13)
_cell_length_b                   6.6058(13)
_cell_length_c                   16.590(3)
_cell_measurement_reflns_used    1708
_cell_measurement_temperature    110(2)
_cell_measurement_theta_max      30.8212
_cell_measurement_theta_min      2.4879
_cell_volume                     694.4(2)
_computing_cell_refinement       'CrystalClear (Rigaku Inc., 2007)'
_computing_data_collection       'CrystalClear (Rigaku Inc., 2007)'
_computing_data_reduction        'CrystalClear (Rigaku Inc., 2007)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      110(2)
_diffrn_measured_fraction_theta_full 0.982
_diffrn_measured_fraction_theta_max 0.982
_diffrn_measurement_device_type  'Rigaku Saturn 70 CCD area detector'
_diffrn_measurement_method       '\w scans'
_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  0.0178
_diffrn_reflns_av_sigmaI/netI    0.0173
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       5
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            9683
_diffrn_reflns_theta_full        28.28
_diffrn_reflns_theta_max         28.28
_diffrn_reflns_theta_min         2.49
_exptl_absorpt_coefficient_mu    0.114
_exptl_absorpt_correction_T_max  0.9754
_exptl_absorpt_correction_T_min  0.9634
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'R. H. Blessing, Acta Cryst. 1995 A51, 33-38'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.427
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             316
_exptl_crystal_size_max          0.33
_exptl_crystal_size_mid          0.22
_exptl_crystal_size_min          0.22
_refine_diff_density_max         0.332
_refine_diff_density_min         -0.215
_refine_diff_density_rms         0.046
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.088
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     214
_refine_ls_number_reflns         3396
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.088
_refine_ls_R_factor_all          0.0445
_refine_ls_R_factor_gt           0.0425
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0564P)^2^+0.2430P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1102
_refine_ls_wR_factor_ref         0.1119
_reflns_number_gt                3233
_reflns_number_total             3396
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c2ce25080b.txt
_cod_data_source_block           PA-HBA
_cod_depositor_comments
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The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
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 
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_cod_database_code               7207675