The supramolecular structure of pyridine-2,6-dicarboxylic acid
Carranza Téllez, Vladimir; Sánchez Gaytán, Brenda; Bernès, Sylvain; González Vergara, Enrique; Acta Crystallographica Section C 58 (2002) o228–o230; doi:10.1107/S0108270102002172

data_2012650
_publ_section_title
;
 The supramolecular structure of pyridine-2,6-dicarboxylic acid
;
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              o228
_journal_page_last               o230
_journal_paper_doi               10.1107/S0108270102002172
_journal_volume                  58
_journal_year                    2002
_chemical_formula_moiety         'C7 H5 N O4'
_chemical_formula_sum            'C7 H5 N O4'
_chemical_formula_weight         167.12
_chemical_melting_point          525
_chemical_name_common            'Dipicolinic acid'
_chemical_name_systematic        '2,6-pyridinedicarboxylic acid'
_space_group_IT_number           11
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yb'
_symmetry_space_group_name_H-M   'P 1 21/m 1'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                90
_cell_angle_beta                 93.156(7)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   3.7663(6)
_cell_length_b                   16.1667(12)
_cell_length_c                   5.5705(4)
_cell_measurement_reflns_used    70
_cell_measurement_temperature    300(2)
_cell_measurement_theta_max      18.39
_cell_measurement_theta_min      3.86
_cell_volume                     338.67(6)
_computing_cell_refinement       XSCANS
_computing_data_collection       'XSCANS (Siemens, 1996)'
_computing_data_reduction        XSCANS
_computing_molecular_graphics    'SHELXTL (Bruker, 1997)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      300(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker P4'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.036
_diffrn_reflns_av_sigmaI/netI    0.023
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -22
_diffrn_reflns_limit_l_max       7
_diffrn_reflns_limit_l_min       -7
_diffrn_reflns_number            3920
_diffrn_reflns_theta_full        29.99
_diffrn_reflns_theta_max         29.99
_diffrn_reflns_theta_min         2.52
_diffrn_standards_decay_%        1
_diffrn_standards_interval_count 97
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.138
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.639
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       irregular
_exptl_crystal_F_000             172
_exptl_crystal_size_max          0.7
_exptl_crystal_size_mid          0.4
_exptl_crystal_size_min          0.4
_refine_diff_density_max         0.34
_refine_diff_density_min         -0.18
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.061
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     74
_refine_ls_number_reflns         1021
_refine_ls_number_restraints     2
_refine_ls_restrained_S_all      1.060
_refine_ls_R_factor_all          0.043
_refine_ls_R_factor_gt           0.040
_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^)+(0.0827P)^2^+0.0236P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.118
_refine_ls_wR_factor_ref         0.121
_reflns_number_gt                937
_reflns_number_total             1021
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            sk1531.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
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_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
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 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_original_sg_symbol_Hall     -P2yb
_cod_original_sg_symbol_H-M      'P 21/m'
_cod_database_code               2012650
_cod_database_fobs_code          2012650