#------------------------------------------------------------------------------
#$Date: 2008-01-14 00:15:36 +0200 (Mon, 14 Jan 2008) $
#$Revision: 14 $
#$URL: file:///home/coder/svn-repositories/cod/cif/2/2014742.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_2014742
_journal_name_full  'Acta Crystallographica, Section C'
_journal_year  2005
_journal_volume  61
_journal_page_first  o118
_journal_page_last  o121
_publ_section_title
;
2,5-Piperazinedione--oxalic acid--water (1/1/2) and a redetermination of
2,5-piperazinedione, both at 120 K: hydrogen-bonded sheets containing multiple
ring types
;
loop_
_publ_author_name
  'Sarangarajan, Thanjavur Ramabhadran'
  'Panchanatheswaran, Krishnaswamy '
  'Low, John N.'
  'Glidewell, Christopher'
_chemical_formula_moiety  'C4 H6 N2 O2'
_chemical_formula_sum  'C4 H6 N2 O2'
_chemical_formula_iupac  'C4 H6 N2 O2'
_chemical_formula_weight  114.11
_symmetry_cell_setting  monoclinic
_symmetry_space_group_name_H-M  'P 21/c'
_symmetry_space_group_name_Hall  '-P 2ybc'
loop_
_symmetry_equiv_pos_as_xyz
  'x, y, z'
  '-x, y+1/2, -z+1/2'
  '-x, -y, -z'
  'x, -y+1/2, z+1/2'
_cell_length_a  3.8967(10)
_cell_length_b  11.527(3)
_cell_length_c  5.159(2)
_cell_angle_alpha  90.00
_cell_angle_beta  96.46(2)
_cell_angle_gamma  90.00
_cell_volume  230.26(12)
_cell_formula_units_Z  2
_cell_measurement_temperature  120(2)
_exptl_crystal_density_diffrn  1.646
_diffrn_ambient_temperature  120(2)
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
_atom_site_adp_type
_atom_site_calc_flag
_atom_site_refinement_flags
_atom_site_occupancy
_atom_site_disorder_assembly
_atom_site_disorder_group
_atom_site_type_symbol
  O2 0.5941(4) 0.63335(11) 0.6680(2) 0.0190(6) Uani d . 1 . . O
  N1 0.8110(4) 0.45696(13) 0.7787(3) 0.0159(6) Uani d . 1 . . N
  C2 0.7821(4) 0.56985(18) 0.8176(3) 0.0148(6) Uani d . 1 . . C
  C3 0.9821(5) 0.62391(14) 1.0532(4) 0.0159(7) Uani d . 1 . . C
  H1 0.6939 0.4281 0.6376 0.019 Uiso calc R 1 . . H
  H3A 1.1366 0.6842 0.9939 0.019 Uiso calc R 1 . . H
  H3B 0.8175 0.6631 1.1572 0.019 Uiso calc R 1 . . H
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
  O2 0.0226(10) 0.0126(9) 0.0206(9) 0.0006(5) -0.0028(6) 0.0012(5)
  N1 0.0191(11) 0.0114(10) 0.0165(9) 0.0000(6) -0.0010(7) -0.0005(5)
  C2 0.0158(11) 0.0122(10) 0.0169(10) -0.0012(6) 0.0042(7) 0.0017(6)
  C3 0.0168(11) 0.0107(10) 0.0198(11) 0.0014(6) -0.0001(7) 0.0001(6)
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_site_symmetry_2
_geom_bond_distance
_geom_bond_publ_flag
  N1 C2 . 1.323(3) no
  N1 C3 3_767 1.454(2) no
  N1 H1 . 0.88 no
  C2 O2 . 1.241(2) no
  C2 C3 . 1.503(3) no
  C3 H3A . 0.99 no
  C3 H3B . 0.99 no