##############################################################################
###                                                                        ###
###        Electronic paper (Acta Crystallographica Section E)             ###
###                                                                        ###
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#                                                                            #
# This CIF contains the data in a paper accepted for publication in Acta     #
# Crystallographica Section E. It conforms to the requirements of Notes      #
# for Authors for Section E, and has been peer reviewed under the auspices   #
# of the IUCr Commission on Journals.                                        #
#                                                                            #
# Full details of the Crystallographic Information File format               #
# are given in the paper "The Crystallographic Information File (CIF):       #
# a New Standard Archive File for Crystallography" by S. R. Hall, F. H.      #
# Allen and I. D. Brown [Acta Cryst. (1991), A47, 655-685].                  #
#                                                                            #
# The current version of the core CIF dictionary is obtainable from          #
# ftp://ftp.iucr.org/pub/cif_core.dic. The current version number is 2.1.    #
#                                                                            #
# Software is freely available for graphical display of the structure(s) in  #
# this CIF.  For information consult the CIF home page http://www.iucr.org/  #
# cif/home.html                                                              #
#                                                                            #
#            Copyright International Union of Crystallography                #
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##############################################################################
                                             
data_global
_audit_creation_method     ' SHELXL97 (Sheldrick, 1997)'
_journal_date_recd_electronic     2006-07-25
_journal_date_accepted     2006-08-07
_journal_name_full     'Acta Crystallographica, Section E'
_journal_year     2006
_journal_volume     62
_journal_issue      9
_journal_page_first     o3912
_journal_page_last     o3914
_journal_paper_category     EO
_journal_coeditor_code     FL2044
_publ_contact_author_name     'Dr Graham Smith'
_publ_contact_author_address
;
    School of Physical and Chemical Sciences
    Queensland University of Technology
    GPO Box 2434, Brisbane, Qld 4001, Australia
;
_publ_contact_author_email     g.smith@qut.edu.au
_publ_contact_author_fax     ' 61 7 3864 1804 '
_publ_contact_author_phone     ' 61 7 3864 2293 '
_publ_section_title
;
Bis(guanidinium) pyrazine-2,3-dicarboxylate trihydrate
;
loop_
    _publ_author_name
    _publ_author_address
    'Graham Smith'
;
School of Physical and Chemical Sciences
Queensland University of Technology
GPO Box 2434
Brisbane
Queensland 4001
Australia
;
    'Urs D. Wermuth'
;
School of Physical and Chemical Sciences
Queensland University of Technology
GPO Box 2434
Brisbane
Queensland 4001
Australia
;
    'David J. Young'
;
School Science
Griffith University
Nathan
Queensland 4111
Australia
;
    'Jonathan M. White'
;
School of Chemistry
University of Melbourne
Parkville
Victoria 3052
Australia
;
data_I
_audit_creation_method     'SHELXL97 (Sheldrick, 1997)'
_chemical_name_systematic
;
Bis(guanidinium) pyrazine-2,3-dicarboxylate trihydrate
;
_chemical_name_common     'guanidinium pyrazine-2,3-dicarboxylate trihydrate'
_chemical_formula_moiety     '2C H6 N3 +, C6 H2 N2 O4 2-, 3H2 O'
_chemical_formula_sum     'C8 H20 N8 O7'
_chemical_formula_weight     340.32
_chemical_melting_point     565
_symmetry_cell_setting     monoclinic
_symmetry_space_group_name_H-M     'P 2/c'
_symmetry_space_group_name_Hall     '-P 2yc'
loop_
    _symmetry_equiv_pos_as_xyz
    'x, y, z'
    '-x, y, -z+1/2'
    '-x, -y, -z'
    'x, -y, z+1/2'
_cell_length_a     7.7141(8)
_cell_length_b     7.7252(8)
_cell_length_c     13.0299(13)
_cell_angle_alpha     90.00
_cell_angle_beta     93.403(2)
_cell_angle_gamma     90.00
_cell_volume     775.12(14)
_cell_formula_units_Z     2
_cell_measurement_reflns_used     1956
_cell_measurement_theta_min     2.64
_cell_measurement_theta_max     27.49
_cell_measurement_temperature     130(2)
_exptl_crystal_description     'block'
_exptl_crystal_colour     'colourless'
_exptl_crystal_size_max     0.35
_exptl_crystal_size_mid     0.30
_exptl_crystal_size_min     0.25
_exptl_crystal_density_diffrn     1.458
_exptl_crystal_density_meas     ?
_exptl_crystal_density_method     'not measured'
_exptl_crystal_F_000     360
_exptl_absorpt_coefficient_mu     0.126
_exptl_absorpt_correction_type     'none'
_exptl_absorpt_process_details     ?
_exptl_absorpt_correction_T_min     ?
_exptl_absorpt_correction_T_max     ?
_exptl_special_details
;
;
_diffrn_ambient_temperature     130(2)
_diffrn_radiation_type     MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_radiation_source     'sealed tube'
_diffrn_radiation_monochromator     'graphite'
_diffrn_measurement_device_type     'Bruker CCD area-detector'
_diffrn_measurement_method     'φ and ω'
_diffrn_detector_area_resol_mean     ?
_diffrn_reflns_number     3904
_diffrn_reflns_av_R_equivalents     0.0389
_diffrn_reflns_av_sigmaI/netI     0.0334
_diffrn_reflns_theta_min     2.64
_diffrn_reflns_theta_max     25.00
_diffrn_reflns_theta_full     25.00
_diffrn_measured_fraction_theta_max     0.998
_diffrn_measured_fraction_theta_full     0.998
_diffrn_reflns_limit_h_min     -9
_diffrn_reflns_limit_h_max     9
_diffrn_reflns_limit_k_min     -9
_diffrn_reflns_limit_k_max     8
_diffrn_reflns_limit_l_min     -15
_diffrn_reflns_limit_l_max     8
_diffrn_standards_number     ?
_diffrn_standards_interval_count     ?
_diffrn_standards_interval_time     ?
_diffrn_standards_decay_%     0.0
_refine_special_details
;
 Refinement of F² against ALL reflections.  The weighted R-factor wR and
 goodness of fit S are based on F², conventional R-factors R are based
 on F, with F set to zero for negative F². The threshold expression of
 F² > 2sigma(F²) is used only for calculating R-factors(gt) etc. and is
 not relevant to the choice of reflections for refinement.  R-factors based
 on F² are statistically about twice as large as those based on F, and R-
 factors based on ALL data will be even larger.
;
_reflns_number_total     1360
_reflns_number_gt     1202
_reflns_threshold_expression     I>2σ(I)
_refine_ls_structure_factor_coef     Fsqd
_refine_ls_matrix_type     full
_refine_ls_R_factor_all     0.0350
_refine_ls_R_factor_gt     0.0311
_refine_ls_wR_factor_gt     0.0832
_refine_ls_wR_factor_ref     0.0851
_refine_ls_goodness_of_fit_ref     1.103
_refine_ls_restrained_S_all     1.103
_refine_ls_number_reflns     1360
_refine_ls_number_parameters     141
_refine_ls_number_restraints     0
_refine_ls_hydrogen_treatment     mixed
_refine_ls_weighting_scheme     calc
_refine_ls_weighting_details
         'calc w=1/[σ²(Fo²)+(0.0474P)²+0.0086P] where P=(Fo²+2Fc²)/3'
_atom_sites_solution_hydrogens     geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary     difmap
_refine_ls_shift/su_max     0.000
_refine_ls_shift/su_mean     0.000
_refine_diff_density_max     0.212
_refine_diff_density_min     -0.161
_refine_ls_extinction_method     'none'
_refine_ls_extinction_coef     ?
_refine_ls_extinction_expression     ?
loop_
    _atom_type_symbol
    _atom_type_description
    _atom_type_scat_dispersion_real
    _atom_type_scat_dispersion_imag
    _atom_type_scat_source
    'C' 'C' 0.0033 0.0016
                         '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' 0.0061 0.0033
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
    'O' 'O' 0.0106 0.0060
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
_computing_data_collection     'SMART (Bruker, 2000)'
_computing_cell_refinement     'SAINT (Bruker, 1999)'
_computing_data_reduction     'SAINT'
_computing_structure_solution     'SHELXS97 (Sheldrick, 1997)'
_computing_structure_refinement     'SHELXL97 (Sheldrick, 1997)'
_computing_molecular_graphics     'PLATON (Spek, 2003)'
_computing_publication_material     'PLATON'
loop_
    _atom_site_type_symbol
    _atom_site_label
    _atom_site_fract_x
    _atom_site_fract_y
    _atom_site_fract_z
    _atom_site_U_iso_or_equiv
    _atom_site_thermal_displace_type
    _atom_site_calc_flag
    _atom_site_refinement_flags
    _atom_site_occupancy
    O O21 0.75174(12) 0.55020(11) 0.10249(7) 0.0209(3) Uani . . 1.000
    O O22 0.80649(12) 0.43969(12) 0.25967(7) 0.0231(3) Uani . . 1.000
    N N1 0.83813(14) 0.86590(14) 0.19627(8) 0.0171(3) Uani . . 1.000
    C C2 0.91909(16) 0.71685(16) 0.22302(10) 0.0154(4) Uani . . 1.000
    C C6 0.91933(17) 1.01324(18) 0.22345(10) 0.0179(4) Uani . . 1.000
    C C21 0.81946(16) 0.55376(17) 0.19303(11) 0.0165(4) Uani . . 1.000
    N N1G 0.47431(16) 0.94365(17) 0.12223(9) 0.0196(4) Uani . . 1.000
    N N2G 0.40920(18) 0.69045(16) 0.03843(10) 0.0248(4) Uani . . 1.000
    N N3G 0.20799(15) 0.90970(17) 0.03598(9) 0.0203(4) Uani . . 1.000
    C C1G 0.36409(17) 0.84835(17) 0.06520(10) 0.0169(4) Uani . . 1.000
    O O1W 0.10220(13) 0.26837(13) 0.05415(9) 0.0234(3) Uani . . 1.000
    O O2W 0.50000 0.24843(18) 0.25000 0.0235(5) Uani . . 1.000
    H H6 0.865 1.120 0.205 0.022 Uiso . . 1.000
    H H11G 0.4487(19) 1.046(2) 0.1450(13) 0.025(4) Uiso . . 1.000
    H H12G 0.576(2) 0.9006(19) 0.1406(12) 0.028(4) Uiso . . 1.000
    H H21G 0.514(2) 0.645(2) 0.0647(14) 0.044(5) Uiso . . 1.000
    H H22G 0.343(2) 0.634(2) -0.0088(14) 0.037(5) Uiso . . 1.000
    H H31G 0.1868(18) 1.029(2) 0.0464(12) 0.024(4) Uiso . . 1.000
    H H32G 0.133(2) 0.843(2) 0.0051(12) 0.024(4) Uiso . . 1.000
    H H11W 0.125(3) 0.334(3) 0.1038(18) 0.064(7) Uiso . . 1.000
    H H12W 0.154(2) 0.331(3) 0.0023(17) 0.061(6) Uiso . . 1.000
    H H21W 0.406(2) 0.324(3) 0.2487(16) 0.057(6) Uiso . . 1.000
loop_
    _atom_site_aniso_label
    _atom_site_aniso_U_11
    _atom_site_aniso_U_22
    _atom_site_aniso_U_33
    _atom_site_aniso_U_12
    _atom_site_aniso_U_13
    _atom_site_aniso_U_23
    O21 0.0239(5) 0.0202(6) 0.0177(5) -0.0025(4) -0.0056(4) -0.0006(4)
    O22 0.0263(6) 0.0203(5) 0.0222(6) -0.0044(4) -0.0030(4) 0.0054(4)
    N1 0.0203(6) 0.0174(6) 0.0135(6) 0.0016(5) 0.0002(5) 0.0004(5)
    C2 0.0181(7) 0.0181(7) 0.0101(7) 0.0008(5) 0.0014(5) 0.0009(5)
    C6 0.0236(7) 0.0158(7) 0.0143(7) 0.0026(6) 0.0025(6) 0.0006(6)
    C21 0.0136(7) 0.0169(7) 0.0188(7) 0.0035(5) -0.0002(6) -0.0008(6)
    N1G 0.0186(7) 0.0187(7) 0.0209(7) 0.0021(5) -0.0034(5) -0.0044(5)
    N2G 0.0246(7) 0.0212(7) 0.0273(7) 0.0035(6) -0.0086(6) -0.0076(6)
    N3G 0.0182(6) 0.0198(7) 0.0224(7) 0.0001(5) -0.0038(5) -0.0021(5)
    C1G 0.0192(7) 0.0183(7) 0.0132(7) -0.0002(6) 0.0015(6) 0.0018(6)
    O1W 0.0278(6) 0.0222(6) 0.0199(6) -0.0036(4) -0.0004(5) -0.0022(5)
    O2W 0.0222(8) 0.0159(7) 0.0323(9) 0.0000 0.0013(7) 0.0000
_geom_special_details
;
 Bond distances, angles etc. have been calculated using the
 rounded fractional coordinates. All su's are estimated
 from the variances of the (full) variance-covariance matrix.
 The cell esds are taken into account in the estimation of
 distances, angles and torsion angles
;
loop_
    _geom_bond_atom_site_label_1
    _geom_bond_atom_site_label_2
    _geom_bond_site_symmetry_1
    _geom_bond_site_symmetry_2
    _geom_bond_distance
    _geom_bond_publ_flag
    O21 C21 . . 1.2618(17) no
    O22 C21 . . 1.2453(17) no
    O1W H11W . . 0.83(2) no
    O1W H12W . . 0.94(2) no
    O2W H21W . . 0.930(19) no
    O2W H21W . 2_655 0.930(19) no
    N1 C2 . . 1.3459(16) no
    N1 C6 . . 1.3368(17) no
    N1G C1G . . 1.3199(18) no
    N2G C1G . . 1.3210(18) no
    N3G C1G . . 1.3286(18) no
    N1G H12G . . 0.872(15) no
    N1G H11G . . 0.871(16) no
    N2G H22G . . 0.890(17) no
    N2G H21G . . 0.928(16) no
    N3G H32G . . 0.857(15) no
    N3G H31G . . 0.947(15) no
    C2 C2 . 2_755 1.3959(18) no
    C2 C21 . . 1.5150(18) no
    C6 C6 . 2_755 1.3876(19) no
    C6 H6 . . 0.950 no
loop_
    _geom_angle_atom_site_label_1
    _geom_angle_atom_site_label_2
    _geom_angle_atom_site_label_3
    _geom_angle_site_symmetry_1
    _geom_angle_site_symmetry_2
    _geom_angle_site_symmetry_3
    _geom_angle
    _geom_angle_publ_flag
    H11W O1W H12W . . . 100(2) no
    H21W O2W H21W . . 2_655 102.3(18) no
    C2 N1 C6 . . . 117.19(11) no
    H11G N1G H12G . . . 118.1(14) no
    C1G N1G H11G . . . 123.1(10) no
    C1G N1G H12G . . . 118.7(10) no
    H21G N2G H22G . . . 121.4(14) no
    C1G N2G H22G . . . 119.1(10) no
    C1G N2G H21G . . . 119.3(10) no
    C1G N3G H31G . . . 117.9(9) no
    H31G N3G H32G . . . 122.3(14) no
    C1G N3G H32G . . . 119.7(11) no
    N1 C2 C21 . . . 115.10(11) no
    N1 C2 C2 . . 2_755 121.18(11) no
    C2 C2 C21 2_755 . . 123.69(11) no
    N1 C6 C6 . . 2_755 121.63(12) no
    O22 C21 C2 . . . 117.98(12) no
    O21 C21 O22 . . . 126.19(12) no
    O21 C21 C2 . . . 115.77(11) no
    C6 C6 H6 2_755 . . 120 no
    N1 C6 H6 . . . 119 no
    N1G C1G N3G . . . 120.33(13) no
    N2G C1G N3G . . . 120.15(13) no
    N1G C1G N2G . . . 119.52(13) no
loop_
    _geom_torsion_atom_site_label_1
    _geom_torsion_atom_site_label_2
    _geom_torsion_atom_site_label_3
    _geom_torsion_atom_site_label_4
    _geom_torsion_site_symmetry_1
    _geom_torsion_site_symmetry_2
    _geom_torsion_site_symmetry_3
    _geom_torsion_site_symmetry_4
    _geom_torsion
    _geom_torsion_publ_flag
    C6 N1 C2 C21 . . . . 178.38(11) no
    C6 N1 C2 C2 . . . 2_755 0.1(2) no
    C2 N1 C6 C6 . . . 2_755 0.32(18) no
    N1 C2 C21 O21 . . . . 45.86(16) no
    N1 C2 C21 O22 . . . . -131.67(12) no
    C2 C2 C21 O21 2_556 . . . 120.47(11) no
    C2 C2 C21 O22 2_556 . . . -57.13(10) no
    N1 C2 C2 N1 . . 2_755 2_755 -0.3(2) no
    N1 C2 C2 C21 . . 2_755 2_755 -178.43(12) no
    C21 C2 C2 C21 . . 2_755 2_755 3.4(2) no
    N1 C6 C6 N1 . . 2_755 2_755 -0.5(2) no
loop_
    _geom_hbond_atom_site_label_D
    _geom_hbond_atom_site_label_H
    _geom_hbond_atom_site_label_A
    _geom_hbond_site_symmetry_A
    _geom_hbond_distance_DH
    _geom_hbond_distance_HA
    _geom_hbond_distance_DA
    _geom_hbond_angle_DHA
    _geom_hbond_publ_flag
    O1W H11W O22 2_655 0.83(2) 2.00(2) 2.8160(15) 167(2) yes
    O1W H12W O21 3_665 0.94(2) 1.83(2) 2.7700(14) 178(2) yes
    O2W H21W O22 2_655 0.930(19) 1.865(18) 2.7845(12) 170(2) yes
    N1G H11G O2W 1_565 0.871(16) 2.100(16) 2.8836(17) 149.3(14) yes
    N1G H11G O2W 2_665 0.871(16) 2.100(16) 2.8836(17) 149.3(14) yes
    N1G H12G N1 . 0.872(15) 2.124(15) 2.9743(17) 164.6(13) yes
    N2G H21G O21 . 0.928(16) 2.009(16) 2.9310(17) 172.3(16) yes
    N2G H22G O21 3_665 0.890(17) 1.986(17) 2.8458(16) 162.0(14) yes
    N3G H31G O1W 1_565 0.947(15) 1.966(15) 2.9021(17) 169.6(13) yes
    N3G H32G O1W 3_565 0.857(15) 2.112(16) 2.9434(16) 163.3(14) yes
