Experimental and theoretical charge density study of polymorphic isonicotinamide-oxalic acid molecular complexes with strong O...H...N hydrogen bonds.
Schmidtmann, Marc; Farrugia, Louis J.; Middlemiss, Derek S.; Gutmann, Matthias J.; McIntyre, Garry J.; Wilson, Chick C.; The journal of physical chemistry. A 113 (2009) 13985–13997; doi:10.1021/jp9067813

data_1516358
_publ_section_title
;
 Experimental and theoretical charge density study of polymorphic
 isonicotinamide-oxalic acid molecular complexes with strong O...H...N
 hydrogen bonds.
;
_journal_issue                   50
_journal_name_full               'The journal of physical chemistry. A'
_journal_page_first              13985
_journal_page_last               13997
_journal_paper_doi               10.1021/jp9067813
_journal_volume                  113
_journal_year                    2009
_chemical_formula_sum            'C14 H14 N4 O6'
_chemical_formula_weight         334.29
_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   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                85.69(5)
_cell_angle_beta                 88.01(5)
_cell_angle_gamma                84.22(4)
_cell_formula_units_Z            1
_cell_length_a                   3.680
_cell_length_b                   7.595(6)
_cell_length_c                   12.501(9)
_cell_measurement_temperature    100(2)
_cell_volume                     346.5(4)
_computing_cell_refinement       LAUEGEN
_computing_data_collection       VIVALDI
_computing_data_reduction        'ARGONNE_BOXES, LAUENORM'
_computing_molecular_graphics    'Bruker AXS XP'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100(2)
_diffrn_measurement_device_type  'VIVALDI LAUE diffraction'
_diffrn_measurement_method       'LAUE diffraction'
_diffrn_radiation_source         'ILL reactor source'
_diffrn_radiation_type           neutron
_diffrn_radiation_wavelength     0.84-1.90
_diffrn_reflns_av_R_equivalents  0.158
_diffrn_reflns_av_sigmaI/netI    0.1224
_diffrn_reflns_limit_h_max       4
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            4633
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.602
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             113
_exptl_crystal_size_max          0.80
_exptl_crystal_size_mid          0.60
_exptl_crystal_size_min          0.40
_refine_diff_density_max         1.672
_refine_diff_density_min         -1.503
_refine_diff_density_rms         0.370
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.214
_refine_ls_hydrogen_treatment    refined
_refine_ls_matrix_type           full
_refine_ls_number_parameters     172
_refine_ls_number_reflns         1915
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.214
_refine_ls_R_factor_all          0.1195
_refine_ls_R_factor_gt           0.0770
_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^)+(0.1000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1654
_refine_ls_wR_factor_ref         0.1750
_reflns_number_gt                1365
_reflns_number_total             1915
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            1-II_neutron.cif
_cod_data_source_block           oxaill2
_cod_original_sg_symbol_H-M      P-1
_cod_database_code               1516358