data_2011969
_journal_name_full  'Acta Crystallographica, Section C'
_journal_year  2001
_journal_volume  57
_journal_page_first  621
_journal_page_last  624
_publ_section_title
;
Linear hydrogen-bonded molecular tapes in the co-crystals of squaric
acid with 4,4'-dipyridylacetylene or 1,2-bis(4-pyridyl)ethylene
;
loop_
_publ_author_name
  'Zaman, Md. Badruz'
  'Tomura, Masaaki'
  'Yamashita, Yoshiro'
_chemical_formula_moiety  'C12 H12 N2 2+ , 2C4 H O4 -'
_chemical_formula_sum  'C20 H14 N2 O8'
_chemical_formula_weight  410.33
_symmetry_cell_setting  triclinic
_symmetry_space_group_name_H-M  'P -1'
loop_
_symmetry_equiv_pos_as_xyz
  'x, y, z'
  '-x, -y, -z'
_cell_length_a  10.2606(9)
_cell_length_b  12.2942(17)
_cell_length_c  3.7749(13)
_cell_angle_alpha  97.845(17)
_cell_angle_beta  98.444(13)
_cell_angle_gamma  67.259(8)
_cell_volume  432.75(17)
_cell_formula_units_Z  1
_cell_measurement_temperature  296(2)
_exptl_crystal_density_diffrn  1.575
_diffrn_ambient_temperature  296(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
  O1  -.08498(13)  .39152(10)  -.4025(4)  .0499(4) Uani d . 1 . . O
  O2  .07016(12)  .11353(10)  -.5637(4)  .0470(3) Uani d . 1 . . O
  O3  .34122(13)  .11285(11)  -.0093(4)  .0544(4) Uani d . 1 . . O
  O4  .19294(12)  .39772(10)  .1499(4)  .0468(3) Uani d . 1 . . O
  N1  .26855(14)  -.10035(11)  -.6755(4)  .0387(3) Uani d . 1 . . N
  C1  .03897(16)  .31522(13)  -.2828(4)  .0351(4) Uani d . 1 . . C
  C2  .10311(16)  .19053(13)  -.3653(4)  .0357(4) Uani d . 1 . . C
  C3  .23000(16)  .18908(14)  -.1131(4)  .0365(4) Uani d . 1 . . C
  C4  .15808(16)  .32048(13)  -.0406(4)  .0352(4) Uani d . 1 . . C
  C5  .43114(15)  -.33416(13)  -.8337(4)  .0327(3) Uani d . 1 . . C
  C6  .28763(17)  -.28698(14)  -.9677(4)  .0376(4) Uani d . 1 . . C
  C7  .20931(16)  -.16988(14)  -.8837(4)  .0395(4) Uani d . 1 . . C
  C8  .40590(17)  -.14148(14)  -.5435(4)  .0385(4) Uani d . 1 . . C
  C9  .48911(16)  -.25872(14)  -.6205(4)  .0362(4) Uani d . 1 . . C
  C10  .52189(16)  -.45890(13)  -.9123(4)  .0368(4) Uani d . 1 . . C
  H1A  -.102(3)  .472(2)  -.278(6)  .063(6) Uiso d . 1 . . H
  H1  .201(3)  -.015(2)  -.617(7)  .075(8) Uiso d . 1 . . H
  H6  .244(2)  -.3352(17) -1.120(5)  .040(5) Uiso d . 1 . . H
  H7  .109(2)  -.1318(19)  -.975(6)  .054(6) Uiso d . 1 . . H
  H8  .4400(19)  -.0845(16)  -.385(5)  .036(4) Uiso d . 1 . . H
  H9  .588(2)  -.2933(19)  -.519(6)  .055(6) Uiso d . 1 . . H
  H10  .622(2)  -.4786(19)  -.818(6)  .057(6) Uiso d . 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
  O1  .0370(6)  .0303(6)  .0636(8)  -.0034(5)  -.0163(5)  -.0066(5)
  O2  .0374(6)  .0313(6)  .0606(8)  -.0092(5)  -.0075(5)  -.0108(5)
  O3  .0392(7)  .0363(6)  .0690(9)  -.0026(5)  -.0135(6)  -.0020(6)
  O4  .0371(6)  .0309(6)  .0605(8)  -.0093(5)  -.0105(5)  -.0083(5)
  N1  .0377(7)  .0279(6)  .0429(7)  -.0072(5)  -.0001(5)  -.0024(5)
  C1  .0316(7)  .0290(7)  .0394(8)  -.0088(6)  -.0021(6)  -.0009(6)
  C2  .0327(7)  .0300(7)  .0402(8)  -.0103(6)  .0004(6)  -.0036(6)
  C3  .0325(7)  .0302(7)  .0413(8)  -.0093(6)  -.0022(6)  -.0015(6)
  C4  .0322(7)  .0286(7)  .0399(8)  -.0092(6)  .0000(6)  -.0024(6)
  C5  .0321(7)  .0301(8)  .0332(7)  -.0105(6)  .0014(6)  -.0010(6)
  C6  .0339(8)  .0335(8)  .0414(8)  -.0131(6)  -.0030(6)  -.0042(6)
  C7  .0312(8)  .0356(8)  .0446(8)  -.0084(6)  -.0029(6)  -.0005(6)
  C8  .0391(8)  .0327(8)  .0405(8)  -.0149(7)  -.0024(6)  -.0044(6)
  C9  .0315(7)  .0328(8)  .0402(8)  -.0114(6)  -.0031(6)  -.0017(6)
  C10  .0337(8)  .0310(8)  .0403(8)  -.0088(6)  .0008(6)  -.0017(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
  O1 C1 . 1.3138(19) yes
  O1 H1A .  .99(2) no
  O2 C2 . 1.2453(19) yes
  O3 C3 . 1.215(2) yes
  O4 C4 . 1.2440(19) yes
  N1 C7 . 1.340(2) yes
  N1 C8 . 1.342(2) yes
  N1 H1 . 1.02(3) no
  C1 C2 . 1.425(2) yes
  C1 C4 . 1.432(2) yes
  C2 C3 . 1.491(2) yes
  C3 C4 . 1.499(2) yes
  C5 C9 . 1.394(2) yes
  C5 C6 . 1.400(2) yes
  C5 C10 . 1.470(2) yes
  C6 C7 . 1.369(2) yes
  C6 H6 .  .96(2) no
  C7 H7 .  .98(2) no
  C8 C9 . 1.378(2) yes
  C8 H8 .  .993(18) no
  C9 H9 .  .98(2) no
  C10 C10 2_643 1.320(3) yes
  C10 H10 .  .98(2) no