Supramolecular Architectures and Helical Water Chains in Cocrystals of Melamine and Aromatic Carboxylic Acids
Zhang, Xiu-Lian; Chen, Xiao-Ming; Crystal Growth & Design 5 (2005) 617–; doi:10.1021/cg0498251

data_4505029
_publ_section_title
;
 Supramolecular Architectures and Helical Water Chains in Cocrystals of
 Melamine and Aromatic Carboxylic Acids
;
_journal_issue                   2
_journal_name_full               'Crystal Growth &amp; Design'
_journal_page_first              617
_journal_paper_doi               10.1021/cg0498251
_journal_volume                  5
_journal_year                    2005
_chemical_formula_sum            'C7 H11 N6 O3'
_chemical_formula_weight         227.22
_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_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 93.366(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   6.7992(8)
_cell_length_b                   20.156(2)
_cell_length_c                   7.0861(8)
_cell_measurement_temperature    273(2)
_cell_volume                     969.44(19)
_computing_cell_refinement       'SHELXTL-Plus (Sheldrick, 1990)'
_computing_data_collection       'SHELXTL-Plus (Sheldrick, 1990)'
_computing_data_reduction        'SHELXTL-Plus (Sheldrick, 1990)'
_computing_molecular_graphics    'SHELXTL V. 6.10 (Sheldrick, 2000)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      273(2)
_diffrn_measured_fraction_theta_full 0.934
_diffrn_measured_fraction_theta_max 0.934
_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  0.0147
_diffrn_reflns_av_sigmaI/netI    0.0193
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -26
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -9
_diffrn_reflns_number            5979
_diffrn_reflns_theta_full        28.22
_diffrn_reflns_theta_max         28.22
_diffrn_reflns_theta_min         2.02
_exptl_absorpt_coefficient_mu    0.094
_exptl_absorpt_correction_T_max  0.9824
_exptl_absorpt_correction_T_min  0.9671
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.168
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             357
_exptl_crystal_size_max          0.36
_exptl_crystal_size_mid          0.32
_exptl_crystal_size_min          0.19
_refine_diff_density_max         0.318
_refine_diff_density_min         -0.201
_refine_diff_density_rms         0.054
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.638
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     189
_refine_ls_number_reflns         2236
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.638
_refine_ls_R_factor_all          0.0530
_refine_ls_R_factor_gt           0.0446
_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^)+(0.1858P)^2^+0.4532P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1389
_refine_ls_wR_factor_ref         0.1587
_reflns_number_gt                1864
_reflns_number_total             2236
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            cg0498251si20040530_094328.cif
_cod_data_source_block           complex_2
_cod_original_cell_volume        969.5(2)
_cod_original_sg_symbol_H-M      'P 2(1)/c'
_cod_database_code               4505029