Variable Temperature Neutron Diffraction Analysis of a Very Short O−H···O Hydrogen Bond in 2,3,5,6-Pyrazinetetracarboxylic Acid Dihydrate: Synthon-Assisted Short Oacid−H···OwaterHydrogen Bonds in a Multicenter Array
Vishweshwar, Peddy; Jagadeesh Babu, N.; Nangia, Ashwini; Mason, Sax A.; Puschmann, Horst; Mondal, Raju; Howard, Judith A. K.; The Journal of Physical Chemistry A 108 (2004) 9406–; doi:10.1021/jp0476848

data_1506835
_publ_section_title
;
 Variable Temperature Neutron Diffraction Analysis of a Very Short
 O&#x2212;H&#x00B7;&#x00B7;&#x00B7;O Hydrogen Bond in
 2,3,5,6-Pyrazinetetracarboxylic Acid Dihydrate:&#x00A0; Synthon-Assisted
 Short Oacid&#x2212;H&#x00B7;&#x00B7;&#x00B7;OwaterHydrogen Bonds in a
 Multicenter Array
;
_journal_issue                   43
_journal_name_full               'The Journal of Physical Chemistry A'
_journal_page_first              9406
_journal_paper_doi               10.1021/jp0476848
_journal_volume                  108
_journal_year                    2004
_chemical_formula_moiety         'C8 H4 N2 O8, 2H2O'
_chemical_formula_sum            'C8 H8 N2 O10'
_chemical_formula_weight         292.16
_chemical_melting_point          480
_chemical_name_common
;
2,3,5,6-pyrazinetetracarboxylic acid dihydrate
;
_chemical_name_systematic
; 
 2,3,5,6-pyrazinetetracarboxylic acid dihydrate
;
_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           SHELXL-97
_cell_angle_alpha                97.911(5)
_cell_angle_beta                 107.546(5)
_cell_angle_gamma                105.718(5)
_cell_formula_units_Z            1
_cell_length_a                   5.4361(10)
_cell_length_b                   6.3699(10)
_cell_length_c                   8.6672(10)
_cell_measurement_reflns_used    716
_cell_measurement_temperature    20(1)
_cell_measurement_theta_max      31.99
_cell_measurement_theta_min      4.03
_cell_volume                     267.48(7)
_computing_cell_refinement       'ILL RAFD9'
_computing_data_collection       'ILL HKLGEN, MAD'
_computing_data_reduction        'ILL RACER'
_computing_molecular_graphics    'ORTEP and PLUTON'
_computing_publication_material  SHELXL-97
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      20(1)
_diffrn_detector_area_resol_mean '0.25 degrees'
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'd9 four-circle diffractometer'
_diffrn_measurement_method       'omega step-scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          neutron
_diffrn_radiation_source         'ILL reactor'
_diffrn_radiation_type           neutron
_diffrn_radiation_wavelength     0.83970
_diffrn_reflns_av_R_equivalents  0.0149
_diffrn_reflns_av_sigmaI/netI    0.0185
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -1
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            1333
_diffrn_reflns_theta_full        32.09
_diffrn_reflns_theta_max         32.09
_diffrn_reflns_theta_min         3.00
_diffrn_standards_decay_%        0
_exptl_absorpt_coefficient_mu    0.000
_exptl_absorpt_correction_T_max  0.9407
_exptl_absorpt_correction_T_min  0.8515
_exptl_absorpt_correction_type   'Gaussian grid'
_exptl_absorpt_process_details   'program DATAP'
_exptl_crystal_colour            'Pale yellow'
_exptl_crystal_density_diffrn    1.813
_exptl_crystal_description       plate
_exptl_crystal_F_000             100
_exptl_crystal_size_max          2.8
_exptl_crystal_size_mid          1.6
_exptl_crystal_size_min          0.6
_refine_diff_density_max         0.318
_refine_diff_density_min         -0.381
_refine_diff_density_rms         0.081
_refine_ls_extinction_coef       0.072(3)
_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   1.222
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     135
_refine_ls_number_reflns         1123
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.222
_refine_ls_R_factor_all          0.0213
_refine_ls_R_factor_gt           0.0198
_refine_ls_shift/su_max          1.510
_refine_ls_shift/su_mean         0.015
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0152P)^2^+0.3048P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0434
_refine_ls_wR_factor_ref         0.0439
_reflns_number_gt                1088
_reflns_number_total             1123
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jp0476848si20040528_030253.cif
_cod_data_source_block           a
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
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 
;
_cod_database_code               1506835