#------------------------------------------------------------------------------
#$Date: 2016-02-18 17:37:37 +0200 (Thu, 18 Feb 2016) $
#$Revision: 176729 $
#$URL: svn://www.crystallography.net/cod/cif/1/50/68/1506833.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/
#
# All data on this site have been placed in the public domain by the
# contributors.
#
data_1506833
loop_
_publ_author_name
'Vishweshwar, Peddy'
'Jagadeesh Babu, N.'
'Nangia, Ashwini'
'Mason, Sax A.'
'Puschmann, Horst'
'Mondal, Raju'
'Howard, Judith A. K.'
_publ_section_title
;
 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
;
_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         C8H4N2O8.2H2O
_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                98.381(5)
_cell_angle_beta                 107.406(5)
_cell_angle_gamma                105.573(5)
_cell_formula_units_Z            1
_cell_length_a                   5.4385(10)
_cell_length_b                   6.3885(10)
_cell_length_c                   8.6809(10)
_cell_measurement_reflns_used    626
_cell_measurement_temperature    100(1)
_cell_measurement_theta_max      31.98
_cell_measurement_theta_min      4.04
_cell_volume                     268.72(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      100(1)
_diffrn_detector_area_resol_mean '0.25 degrees'
_diffrn_measured_fraction_theta_full 0.941
_diffrn_measured_fraction_theta_max 0.941
_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  0.0200
_diffrn_reflns_av_sigmaI/netI    0.0234
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -1
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            3123
_diffrn_reflns_theta_full        40.14
_diffrn_reflns_theta_max         40.14
_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  0.8414
_exptl_absorpt_correction_type   'Gaussian grid'
_exptl_absorpt_process_details   'program DATAP'
_exptl_crystal_colour            'Pale yellow'
_exptl_crystal_density_diffrn    1.804
_exptl_crystal_density_method    'not measured'
_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         0.456
_refine_diff_density_min         -0.446
_refine_diff_density_rms         0.112
_refine_ls_extinction_coef       0.068(2)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.168
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     135
_refine_ls_number_reflns         1915
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.168
_refine_ls_R_factor_all          0.0271
_refine_ls_R_factor_gt           0.0233
_refine_ls_shift/su_max          1.741
_refine_ls_shift/su_mean         0.022
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[σ²(Fo²)+(0.0128P)²+0.3065P] where P=(Fo²+2Fc²)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0447
_refine_ls_wR_factor_ref         0.0460
_reflns_number_gt                1762
_reflns_number_total             1915
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jp0476848si20040528_025757.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               1506833
loop_
_symmetry_equiv_pos_as_xyz
'x, y, z'
'-x, -y, -z'
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
_atom_site_adp_type
_atom_site_occupancy
_atom_site_symmetry_multiplicity
_atom_site_calc_flag
_atom_site_refinement_flags
O1 O 0.25450(12) -0.05028(9) 0.09056(7) 0.01120(18) Uani 1.000(5) 1 d .
O14 O 0.18328(12) 0.29010(9) 0.21947(7) 0.01111(18) Uani 1.000(5) 1 d .
O3 O 0.63542(12) 0.00209(10) 0.30668(7) 0.01392(11) Uani 1 1 d .
O4 O 0.74737(13) -0.38760(11) 0.44466(7) 0.01692(12) Uani 1 1 d .
O5 O 1.09781(12) -0.21995(11) 0.37021(7) 0.0152(2) Uani 1.000(5) 1 d .
N7 N 0.31070(7) -0.40405(5) -0.07627(4) 0.00808(8) Uani 1 1 d .
H2 H 0.2334(2) 0.09555(19) 0.15640(14) 0.0219(4) Uani 1.000(9) 1 d .
H5 H 1.2024(3) -0.1683(2) 0.49106(15) 0.0266(4) Uani 0.978(9) 1 d P
C8 C 0.46105(10) -0.10288(7) 0.17192(5) 0.00823(9) Uani 1 1 d .
C9 C 0.47875(9) -0.31477(7) 0.08158(5) 0.00732(8) Uani 1 1 d .
C10 C 0.66868(9) -0.41229(7) 0.15868(5) 0.00735(9) Uani 1 1 d .
C11 C 0.84240(9) -0.33366(7) 0.34170(5) 0.00854(9) Uani 1 1 d .
H12 H 0.2214(3) 0.3302(3) 0.33805(15) 0.0307(4) Uani 1.000(9) 1 d .
H13 H -0.0007(3) 0.2892(2) 0.16408(16) 0.0256(4) Uani 1.000(9) 1 d .
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_23
_atom_site_aniso_U_13
_atom_site_aniso_U_12
O1 0.0121(3) 0.0115(2) 0.0082(2) -0.00038(16) 0.00001(17) 0.00651(18)
O14 0.0107(3) 0.0124(3) 0.0087(2) -0.00028(16) 0.00111(18) 0.00567(18)
O3 0.0128(2) 0.0136(2) 0.0088(2) -0.00456(17) -0.00240(18) 0.00507(18)
O4 0.0142(2) 0.0243(3) 0.0059(2) 0.00269(18) 0.00170(18) -0.0010(2)
O5 0.0094(3) 0.0221(3) 0.0077(3) 0.00019(18) 0.00016(18) 0.0002(2)
N7 0.00844(14) 0.00867(12) 0.00498(12) 0.00000(9) -0.00023(10) 0.00329(10)
H2 0.0229(6) 0.0219(5) 0.0188(5) 0.0021(4) 0.0045(4) 0.0092(4)
H5 0.0192(6) 0.0366(7) 0.0129(5) 0.0008(4) -0.0013(4) 0.0026(4)
C8 0.00839(18) 0.00821(16) 0.00600(16) -0.00036(13) 0.00055(14) 0.00285(13)
C9 0.00762(17) 0.00764(16) 0.00478(15) 0.00007(12) 0.00006(13) 0.00270(13)
C10 0.00775(18) 0.00811(16) 0.00444(16) 0.00026(12) 0.00010(13) 0.00289(13)
C11 0.00848(19) 0.00976(16) 0.00495(16) 0.00025(12) 0.00025(13) 0.00246(14)
H12 0.0372(8) 0.0390(7) 0.0140(5) 0.0006(4) 0.0037(4) 0.0189(6)
H13 0.0175(6) 0.0339(6) 0.0234(6) 0.0053(4) 0.0020(4) 0.0120(4)
loop_
_atom_type_symbol
_atom_type_description
_atom_type_scat_dispersion_real
_atom_type_scat_dispersion_imag
_atom_type_scat_source
C C 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
N N 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
O O 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
loop_
_geom_angle_atom_site_label_1
_geom_angle_atom_site_label_2
_geom_angle_atom_site_label_3
_geom_angle
_geom_angle_site_symmetry_1
C8 O1 H2 114.08(8) .
H2 O14 H12 116.93(11) .
H2 O14 H13 113.60(10) .
H12 O14 H13 107.23(13) .
C11 O5 H5 110.57(9) .
C10 N7 C9 117.93(3) 2_645
O3 C8 O1 126.85(5) .
O3 C8 C9 119.80(5) .
O1 C8 C9 113.34(4) .
N7 C9 C10 121.05(4) .
N7 C9 C8 117.63(4) .
C10 C9 C8 121.31(4) .
N7 C10 C9 121.02(4) 2_645
N7 C10 C11 115.43(4) 2_645
C9 C10 C11 123.29(4) .
O4 C11 O5 126.16(5) .
O4 C11 C10 120.43(5) .
O5 C11 C10 113.26(4) .
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_distance
_geom_bond_site_symmetry_2
O1 C8 1.2926(7) .
O1 H2 1.0721(12) .
O14 H2 1.4112(13) .
O14 H12 0.9670(13) .
O14 H13 0.9700(12) .
O3 C8 1.2181(7) .
O4 C11 1.2063(7) .
O5 C11 1.3110(8) .
O5 H5 0.9871(12) .
N7 C10 1.3322(5) 2_645
N7 C9 1.3346(5) .
C8 C9 1.5041(6) .
C9 C10 1.3988(6) .
C10 N7 1.3322(5) 2_645
C10 C11 1.5112(6) .
