Statistically disordered short hydrogen bonds in (pipzH~2~)(cdoH)~2~ and a comparison with (pipzH~2~)(cdo)·H~2~O (pipz is piperazine and cdoH~2~ is chelidonic acid)
Ghadermazi, Mohammad; Olmstead, Marilyn M.; Attar Gharamaleki, Jafar; Rostami, Shahideh; Acta Crystallographica Section C 67 (2011) o134–o138; doi:10.1107/S0108270111008110

data_2018047
_publ_section_title
;
 Statistically disordered short hydrogen bonds in (pipzH~2~)(cdoH)~2~
 and a comparison with (pipzH~2~)(cdo)&#x00B7;H~2~O (pipz is piperazine
 and cdoH~2~ is chelidonic acid)
;
_journal_coeditor_code           SK3402
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              o134
_journal_page_last               o138
_journal_paper_doi               10.1107/S0108270111008110
_journal_volume                  67
_journal_year                    2011
_chemical_formula_iupac          'C4 H12 N2 2+ , 2C7 H3 O6 -'
_chemical_formula_moiety         'C4 H12 N2 2+, 2(C7 H3 O6 -)'
_chemical_formula_sum            'C18 H18 N2 O12'
_chemical_formula_weight         454.34
_chemical_name_common            (pipH~2~)(cdoH)~2~
_chemical_name_systematic
;
piperazine-1,4-diium bis(6-carboxy-4-oxo-4<i>H</i>-pyran-2-carboxylate)
;
_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   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                90.377(2)
_cell_angle_beta                 94.110(2)
_cell_angle_gamma                104.538(3)
_cell_formula_units_Z            1
_cell_length_a                   6.7880(3)
_cell_length_b                   8.0650(4)
_cell_length_c                   8.5675(4)
_cell_measurement_reflns_used    5711
_cell_measurement_temperature    87(2)
_cell_measurement_theta_max      31.5
_cell_measurement_theta_min      2.6
_cell_volume                     452.70(4)
_computing_cell_refinement       'SAINT (Bruker, 2010)'
_computing_data_collection       'APEX2 (Bruker, 2010)'
_computing_data_reduction        'SAINT (Bruker, 2010)'
_computing_molecular_graphics    'XP in SHELXTL (Sheldrick, 2008)'
_computing_publication_material  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      87(2)
_diffrn_detector_area_resol_mean 8.3
_diffrn_measured_fraction_theta_full 0.986
_diffrn_measured_fraction_theta_max 0.986
_diffrn_measurement_device_type  'Bruker SMART APEXII'
_diffrn_measurement_method       \w
_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  0.0114
_diffrn_reflns_av_sigmaI/netI    0.0124
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            7496
_diffrn_reflns_theta_full        31.54
_diffrn_reflns_theta_max         31.54
_diffrn_reflns_theta_min         2.38
_exptl_absorpt_coefficient_mu    0.143
_exptl_absorpt_correction_T_max  0.976
_exptl_absorpt_correction_T_min  0.956
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 1996)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.667
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             236
_exptl_crystal_size_max          0.36
_exptl_crystal_size_mid          0.34
_exptl_crystal_size_min          0.22
_refine_diff_density_max         0.529
_refine_diff_density_min         -0.235
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.056
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     153
_refine_ls_number_reflns         2971
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.056
_refine_ls_R_factor_all          0.0328
_refine_ls_R_factor_gt           0.0313
_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^)+(0.0569P)^2^+0.1111P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0909
_refine_ls_wR_factor_ref         0.0923
_reflns_number_gt                2806
_reflns_number_total             2971
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            sk3402.cif
_cod_data_source_block           II
_cod_database_code               2018047
_cod_database_fobs_code          2018047