3,4-Di-2-pyridyl-1,2,5-oxadiazole and its perchlorate salt
Liu, Na; Cheng, Ai-Ling; Gao, En-Qing; Acta Crystallographica Section C 63 (2007) o93–o95; doi:10.1107/S0108270106052401

data_2015785
_publ_section_title
;
 3,4-Di-2-pyridyl-1,2,5-oxadiazole and its perchlorate salt
;
_journal_coeditor_code           FA3049
_journal_issue                   2
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              o93
_journal_page_last               o95
_journal_paper_doi               10.1107/S0108270106052401
_journal_volume                  63
_journal_year                    2007
_chemical_formula_iupac          'C12 H8 N4 O'
_chemical_formula_moiety         'C12 H8 N4 O'
_chemical_formula_sum            'C12 H8 N4 O'
_chemical_formula_weight         224.22
_chemical_name_systematic
;
3,4-di-2-pyridyl-1,2,5-oxadiazole
;
_space_group_IT_number           43
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'F 2 -2d'
_symmetry_space_group_name_H-M   'F d d 2'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   13.0702(8)
_cell_length_b                   21.8905(16)
_cell_length_c                   7.7957(5)
_cell_measurement_reflns_used    7309
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      27.485
_cell_measurement_theta_min      3.395
_cell_volume                     2230.5(3)
_computing_cell_refinement       'HKL SCALEPACK (Otwinowski & Minor, 1997)'
_computing_data_collection       'COLLECT (Nonius, 1998)'
_computing_data_reduction
'HKL DENZO (Otwinowski & Minor, 1997) and MAXUS (Mackay <i>et al.</i>,  1998)'
_computing_molecular_graphics    'SHELXTL (Sheldrick, 1997b)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997a)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997a)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean 0.76
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type  'Nonius KappaCCD area-detector'
_diffrn_measurement_method       '\f and \w'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
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_diffrn_reflns_av_R_equivalents  0.0933
_diffrn_reflns_av_sigmaI/netI    0.0706
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       28
_diffrn_reflns_limit_k_min       -28
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            8433
_diffrn_reflns_theta_full        27.40
_diffrn_reflns_theta_max         27.40
_diffrn_reflns_theta_min         3.63
_diffrn_standards_decay_%        0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.091
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.335
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       rod
_exptl_crystal_F_000             928
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.125
_refine_diff_density_min         -0.168
_refine_ls_extinction_coef       0.0037(6)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 1997a)'
_refine_ls_goodness_of_fit_ref   1.099
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     79
_refine_ls_number_reflns         676
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.098
_refine_ls_R_factor_all          0.1392
_refine_ls_R_factor_gt           0.0650
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0334P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0716
_refine_ls_wR_factor_ref         0.0828
_reflns_number_gt                398
_reflns_number_total             676
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            fa3049.cif
_cod_data_source_block           I
_cod_original_sg_symbol_Hall     F2-2d
_cod_database_code               2015785
_cod_database_fobs_code          2015785