Importance of Solvent Selection for Stoichiometrically Diverse Cocrystal Systems: Caffeine/Maleic Acid 1:1 and 2:1 Cocrystals
Leyssens, Tom; Springuel, Geraldine; Montis, Riccardo; Candoni, Nadine; Veesler, Stéphane; Crystal Growth & Design 12 (2012) 1520–1530; doi:10.1021/cg201581z

data_4505576
_publ_section_title
;
 Importance of Solvent Selection for Stoichiometrically Diverse Cocrystal
 Systems: Caffeine/Maleic Acid 1:1 and 2:1 Cocrystals
;
_journal_coden_ASTM              CGDEFU
_journal_issue                   3
_journal_name_full               'Crystal Growth & Design'
_journal_page_first              1520
_journal_page_last               1530
_journal_paper_doi               10.1021/cg201581z
_journal_volume                  12
_journal_year                    2012
_chemical_formula_sum            'C12 H14 N4 O6'
_chemical_formula_weight         310.27
_space_group_IT_number           2
_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                77.59(3)
_cell_angle_beta                 77.68(3)
_cell_angle_gamma                69.92(3)
_cell_formula_units_Z            2
_cell_length_a                   7.9765(18)
_cell_length_b                   8.067(3)
_cell_length_c                   12.162(5)
_cell_measurement_temperature    293(2)
_cell_volume                     709.5(5)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.972
_diffrn_measured_fraction_theta_max 0.967
_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  0.0648
_diffrn_reflns_av_sigmaI/netI    0.0501
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            11302
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.71
_diffrn_reflns_theta_min         2.72
_exptl_absorpt_coefficient_mu    0.118
_exptl_crystal_density_diffrn    1.452
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             324
_refine_diff_density_max         0.337
_refine_diff_density_min         -0.390
_refine_diff_density_rms         0.098
_refine_ls_extinction_coef       0.144(19)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.087
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     205
_refine_ls_number_reflns         2615
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.087
_refine_ls_R_factor_all          0.0629
_refine_ls_R_factor_gt           0.0591
_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^)+(0.1026P)^2^+0.1841P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1638
_refine_ls_wR_factor_ref         0.1688
_reflns_number_gt                2331
_reflns_number_total             2615
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            cg201581z_si_003.cif
_cod_data_source_block           tlset8
_cod_original_cell_volume        709.4(4)
_cod_database_code               4505576