data_try _audit_creation_method SHELXL-97 _chemical_name_systematic ; ? ; _chemical_name_common 'melamine + uracil' _chemical_melting_point ? _chemical_formula_moiety 'C3 H6 N6, C4 H4 N2 O2' _chemical_formula_sum 'C7 H10 N8 O2' _chemical_formula_weight 238.23 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' _symmetry_cell_setting 'Monoclinic' _symmetry_space_group_name_H-M 'C2/c' loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y, -z+1/2' 'x+1/2, y+1/2, z' '-x+1/2, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y, z-1/2' '-x+1/2, -y+1/2, -z' 'x+1/2, -y+1/2, z-1/2' _cell_length_a 14.3618(10) _cell_length_b 7.5472(6) _cell_length_c 18.9922(14) _cell_angle_alpha 90.00 _cell_angle_beta 91.838(4) _cell_angle_gamma 90.00 _cell_volume 2057.5(3) _cell_formula_units_Z 8 _cell_measurement_temperature 273(2) _cell_measurement_reflns_used 145 _cell_measurement_theta_min 2 _cell_measurement_theta_max 25 _exptl_crystal_description 'rods' _exptl_crystal_colour 'colourless' _exptl_crystal_size_max 0.27 _exptl_crystal_size_mid 0.22 _exptl_crystal_size_min 0.15 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.538 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 992 _exptl_absorpt_coefficient_mu 0.120 _exptl_absorpt_correction_type 'none' _exptl_absorpt_correction_T_min ? _exptl_absorpt_correction_T_max ? _exptl_absorpt_process_details ? _exptl_special_details ; ? ; _diffrn_ambient_temperature 273(2) _diffrn_radiation_wavelength 0.71073 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device_type 'Siemens Smart CCD diffractometer' _diffrn_measurement_method 'W scans' _diffrn_detector_area_resol_mean ? _diffrn_standards_number ? _diffrn_standards_interval_count ? _diffrn_standards_interval_time ? _diffrn_standards_decay_% ? _diffrn_reflns_number 4727 _diffrn_reflns_av_R_equivalents 0.0282 _diffrn_reflns_av_sigmaI/netI 0.0339 _diffrn_reflns_limit_h_min -17 _diffrn_reflns_limit_h_max 17 _diffrn_reflns_limit_k_min -9 _diffrn_reflns_limit_k_max 7 _diffrn_reflns_limit_l_min -22 _diffrn_reflns_limit_l_max 22 _diffrn_reflns_theta_min 2.15 _diffrn_reflns_theta_max 25.39 _reflns_number_total 1861 _reflns_number_gt 1543 _reflns_threshold_expression >2sigma(I) _computing_data_collection 'Siemns SMART' _computing_cell_refinement 'HKL' _computing_data_reduction 'HKL' _computing_structure_solution 'SHELXTL97' _computing_structure_refinement 'SHELXL-97 (Sheldrick, 1997)' _computing_molecular_graphics ? _computing_publication_material 'SHELXTL97' _refine_special_details ; Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2sigma(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.0736P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment mixed _refine_ls_extinction_method SHELXL _refine_ls_extinction_coef 0.033(2) _refine_ls_extinction_expression 'Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^' _refine_ls_number_reflns 1861 _refine_ls_number_parameters 195 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.0443 _refine_ls_R_factor_gt 0.0373 _refine_ls_wR_factor_ref 0.1089 _refine_ls_wR_factor_gt 0.1053 _refine_ls_goodness_of_fit_ref 1.043 _refine_ls_restrained_S_all 1.043 _refine_ls_shift/su_max 0.000 _refine_ls_shift/su_mean 0.000 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 _atom_site_disorder_assembly _atom_site_disorder_group N5 N 0.62134(9) 0.10016(18) 0.57910(7) 0.0426(4) Uani 1 1 d . . . N2 N 0.83388(8) -0.07115(17) 0.50089(6) 0.0405(3) Uani 1 1 d . . . O2 O 0.71679(7) 0.08107(15) 0.44482(5) 0.0485(3) Uani 1 1 d . . . N8 N 0.60723(8) 0.02642(16) 0.69523(6) 0.0365(3) Uani 1 1 d . . . N6 N 0.74881(8) -0.02204(16) 0.63454(6) 0.0364(3) Uani 1 1 d . . . N7 N 0.74120(8) -0.09179(17) 0.75642(6) 0.0390(3) Uani 1 1 d . . . O1 O 0.94496(8) -0.22806(18) 0.55922(6) 0.0564(4) Uani 1 1 d . . . N1 N 0.83590(9) -0.02534(18) 0.38105(6) 0.0425(3) Uani 1 1 d . . . C4 C 0.91796(11) -0.1160(2) 0.37882(8) 0.0460(4) Uani 1 1 d . . . C6 C 0.78605(9) -0.07901(18) 0.69574(7) 0.0345(3) Uani 1 1 d . . . N3 N 0.87690(9) -0.1249(2) 0.69775(7) 0.0469(4) Uani 1 1 d . . . N4 N 0.60185(10) -0.0644(2) 0.81005(7) 0.0487(4) Uani 1 1 d . . . C7 C 0.65989(9) 0.03451(18) 0.63742(7) 0.0333(3) Uani 1 1 d . . . C5 C 0.65091(9) -0.04250(19) 0.75220(7) 0.0362(4) Uani 1 1 d . . . C3 C 0.91516(10) -0.1680(2) 0.50274(8) 0.0415(4) Uani 1 1 d . . . C2 C 0.95847(11) -0.1867(2) 0.43590(8) 0.0485(4) Uani 1 1 d . . . C1 C 0.79059(10) 0.0000(2) 0.44230(7) 0.0381(4) Uani 1 1 d . . . H7 H 0.9000(14) -0.157(3) 0.6553(11) 0.067(6) Uiso 1 1 d . . . H3 H 0.9433(12) -0.128(2) 0.3338(9) 0.050(4) Uiso 1 1 d . . . H9 H 0.6530(12) 0.102(2) 0.5413(10) 0.046(5) Uiso 1 1 d . . . H2 H 0.8065(13) -0.056(2) 0.5422(11) 0.057(5) Uiso 1 1 d . . . H4 H 1.0142(15) -0.258(3) 0.4338(10) 0.074(6) Uiso 1 1 d . . . H10 H 0.5650(13) 0.141(2) 0.5803(8) 0.044(4) Uiso 1 1 d . . . H6 H 0.5482(14) -0.026(2) 0.8098(9) 0.054(5) Uiso 1 1 d . . . H8 H 0.8949(12) -0.194(2) 0.7341(10) 0.054(5) Uiso 1 1 d . . . H1 H 0.8079(12) 0.019(2) 0.3416(11) 0.051(5) Uiso 1 1 d . . . H5 H 0.6299(12) -0.088(2) 0.8482(10) 0.042(4) Uiso 1 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 N5 0.0357(7) 0.0610(9) 0.0316(7) 0.0077(6) 0.0064(5) 0.0123(6) N2 0.0364(7) 0.0560(8) 0.0292(7) -0.0004(5) 0.0043(5) 0.0073(5) O2 0.0426(6) 0.0690(8) 0.0339(6) 0.0041(5) 0.0025(4) 0.0114(5) N8 0.0323(6) 0.0476(7) 0.0299(6) -0.0004(5) 0.0053(4) 0.0015(5) N6 0.0340(6) 0.0451(7) 0.0303(6) 0.0025(5) 0.0055(4) 0.0065(5) N7 0.0370(6) 0.0516(8) 0.0287(6) 0.0022(5) 0.0039(5) 0.0044(5) O1 0.0500(7) 0.0785(8) 0.0409(7) 0.0031(5) 0.0016(5) 0.0248(6) N1 0.0470(7) 0.0520(8) 0.0288(7) -0.0004(5) 0.0049(5) -0.0002(6) C4 0.0509(9) 0.0522(9) 0.0356(9) -0.0081(7) 0.0137(7) -0.0017(7) C6 0.0355(7) 0.0382(8) 0.0300(7) -0.0005(5) 0.0036(5) 0.0021(5) N3 0.0383(7) 0.0682(9) 0.0345(7) 0.0081(7) 0.0044(5) 0.0135(6) N4 0.0365(7) 0.0793(11) 0.0308(7) 0.0091(6) 0.0070(6) 0.0047(7) C7 0.0336(7) 0.0357(7) 0.0307(7) -0.0014(5) 0.0042(5) 0.0008(5) C5 0.0362(7) 0.0431(8) 0.0296(7) -0.0015(6) 0.0037(5) -0.0023(6) C3 0.0387(8) 0.0485(9) 0.0373(8) -0.0040(6) 0.0025(6) 0.0034(6) C2 0.0445(9) 0.0554(10) 0.0461(9) -0.0087(7) 0.0100(7) 0.0075(7) C1 0.0386(8) 0.0459(9) 0.0300(7) -0.0016(6) 0.0028(5) -0.0035(6) _geom_special_details ; All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag N5 C7 1.3190(18) . ? N5 H9 0.862(18) . ? N5 H10 0.867(18) . ? N2 C1 1.3672(19) . ? N2 C3 1.3768(19) . ? N2 H2 0.90(2) . ? O2 C1 1.2258(17) . ? N8 C5 1.3385(19) . ? N8 C7 1.3545(17) . ? N6 C6 1.3350(18) . ? N6 C7 1.3492(17) . ? N7 C6 1.3416(18) . ? N7 C5 1.3490(18) . ? O1 C3 1.2286(18) . ? N1 C1 1.3645(18) . ? N1 C4 1.365(2) . ? N1 H1 0.90(2) . ? C4 C2 1.326(2) . ? C4 H3 0.944(18) . ? C6 N3 1.3492(19) . ? N3 H7 0.91(2) . ? N3 H8 0.898(18) . ? N4 C5 1.3343(18) . ? N4 H6 0.82(2) . ? N4 H5 0.837(19) . ? C3 C2 1.438(2) . ? C2 H4 0.97(2) . ? 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 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C7 N5 H9 119.2(11) . . ? C7 N5 H10 118.5(11) . . ? H9 N5 H10 122.3(16) . . ? C1 N2 C3 126.34(12) . . ? C1 N2 H2 117.4(12) . . ? C3 N2 H2 116.3(12) . . ? C5 N8 C7 114.42(12) . . ? C6 N6 C7 114.83(11) . . ? C6 N7 C5 114.61(12) . . ? C1 N1 C4 122.19(13) . . ? C1 N1 H1 116.3(11) . . ? C4 N1 H1 121.5(11) . . ? C2 C4 N1 122.22(13) . . ? C2 C4 H3 122.1(10) . . ? N1 C4 H3 115.7(10) . . ? N6 C6 N7 125.52(13) . . ? N6 C6 N3 117.87(12) . . ? N7 C6 N3 116.60(12) . . ? C6 N3 H7 114.9(12) . . ? C6 N3 H8 115.2(11) . . ? H7 N3 H8 114.8(16) . . ? C5 N4 H6 118.1(13) . . ? C5 N4 H5 119.1(11) . . ? H6 N4 H5 120.3(17) . . ? N5 C7 N6 117.21(12) . . ? N5 C7 N8 117.86(12) . . ? N6 C7 N8 124.92(12) . . ? N4 C5 N8 117.89(13) . . ? N4 C5 N7 116.67(13) . . ? N8 C5 N7 125.44(12) . . ? O1 C3 N2 119.31(13) . . ? O1 C3 C2 125.87(14) . . ? N2 C3 C2 114.82(14) . . ? C4 C2 C3 119.43(15) . . ? C4 C2 H4 122.1(12) . . ? C3 C2 H4 118.3(12) . . ? O2 C1 N1 122.67(13) . . ? O2 C1 N2 122.38(12) . . ? N1 C1 N2 114.95(13) . . ? _diffrn_measured_fraction_theta_max 0.982 _diffrn_reflns_theta_full 25.39 _diffrn_measured_fraction_theta_full 0.982 _refine_diff_density_max 0.160 _refine_diff_density_min -0.214 _refine_diff_density_rms 0.048