Polymorphism in pyridine-2,6-dicarboxylic acid: Competition between “robust” synthons
Grossel, Martin C.; Dwyer, Andrew N.; Hursthouse, Michael B.; Orton, James B.; CrystEngComm 8 (2006) 123–; doi:10.1039/b516387k

data_7203214
_publ_section_title
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 Polymorphism in pyridine-2,6-dicarboxylic acid: Competition between
 &#x201C;robust&#x201D; synthons
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_journal_issue                   2
_journal_name_full               CrystEngComm
_journal_page_first              123
_journal_paper_doi               10.1039/b516387k
_journal_volume                  8
_journal_year                    2006
_chemical_formula_sum            'C7 H4 N O4'
_chemical_formula_weight         166.11
_chemical_name_systematic
;
?
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_space_group_IT_number           33
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2n'
_symmetry_space_group_name_H-M   'P n a 21'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   14.034(10)
_cell_length_b                   13.205(17)
_cell_length_c                   3.699(8)
_cell_measurement_temperature    120(2)
_cell_volume                     685.5(18)
_computing_cell_refinement
' DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998)'
_computing_data_collection       ' DENZO (Otwinowski and Minor, 1997)'
_computing_data_reduction
' DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998)'
_computing_molecular_graphics    'PLATON (Spek, 1990)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997b)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997a)'
_diffrn_ambient_temperature      120(2)
_diffrn_detector_area_resol_mean 9.091
_diffrn_measured_fraction_theta_full 0.977
_diffrn_measured_fraction_theta_max 0.977
_diffrn_measurement_device_type  'Nonius KappaCCD Area Detector'
_diffrn_measurement_method       '\f and \w scans to fill Ewald Sphere'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Nonius FR591 rotating anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0508
_diffrn_reflns_av_sigmaI/netI    0.0525
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       4
_diffrn_reflns_limit_l_min       -4
_diffrn_reflns_number            6128
_diffrn_reflns_theta_full        27.46
_diffrn_reflns_theta_max         27.46
_diffrn_reflns_theta_min         3.41
_exptl_absorpt_coefficient_mu    0.136
_exptl_absorpt_correction_T_max  0.9986
_exptl_absorpt_correction_T_min  0.9946
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SORTAV Blessing (1997)'
_exptl_crystal_colour            Colourless
_exptl_crystal_density_diffrn    1.610
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Plate
_exptl_crystal_F_000             340
_exptl_crystal_size_max          0.04
_exptl_crystal_size_mid          0.04
_exptl_crystal_size_min          0.01
_refine_diff_density_max         0.389
_refine_diff_density_min         -0.447
_refine_diff_density_rms         0.071
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   3(2)
_refine_ls_extinction_coef       0.047(16)
_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   1.039
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     114
_refine_ls_number_reflns         1543
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.039
_refine_ls_R_factor_all          0.0759
_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^)+(0.1147P)^2^+0.0922P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1573
_refine_ls_wR_factor_ref         0.1701
_reflns_number_gt                1275
_reflns_number_total             1543
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b516387k.txt
_cod_data_source_block           s97
_cod_depositor_comments
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The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
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_enum 1527 2010-12-29 10:47:43Z saulius 
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_cod_original_sg_symbol_H-M      Pna2(1)
_cod_database_code               7203214