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#$Date: 2016-02-20 05:06:23 +0200 (Sat, 20 Feb 2016) $
#$Revision: 176774 $
#$URL: svn://www.crystallography.net/cod/cif/2/20/13/2201315.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/. The original data for this entry
# were provided by IUCr Journals, http://journals.iucr.org/.
#
# The file may be used within the scientific community so long as
# proper attribution is given to the journal article from which the
# data were obtained.
#
data_2201315
loop_
_publ_author_name
'Näther, Christian'
'Kowallik, Petra'
'Jeß, Inke'
_publ_section_title
;
 Pyrazine N,N'-dioxide
;
_journal_issue                   11
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o1253
_journal_page_last               o1254
_journal_paper_doi               10.1107/S1600536802018883
_journal_volume                  58
_journal_year                    2002
_chemical_formula_iupac          'C4 H4 N2 O2'
_chemical_formula_moiety         'C4 H4 N2 O2'
_chemical_formula_sum            'C4 H4 N2 O2'
_chemical_formula_weight         112.09
_chemical_name_common            'Pyrazine dioxide'
_chemical_name_systematic
;
Pyrazine N,N'-dioxide
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 96.778(19)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   3.7376(6)
_cell_length_b                   11.0011(18)
_cell_length_c                   5.7184(9)
_cell_measurement_reflns_used    1392
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      28
_cell_measurement_theta_min      4
_cell_volume                     233.48(7)
_computing_cell_refinement       'IPDS Program Package'
_computing_data_collection       'IPDS Program Package (Stoe & Cie, 1998)'
_computing_data_reduction        'IPDS Program Package'
_computing_molecular_graphics    'XP in SHELXTL (Bruker, 1998)'
_computing_publication_material  'CIFTAB in SHELXL97'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.977
_diffrn_measured_fraction_theta_max 0.977
_diffrn_measurement_device_type  'Stoe IPDS'
_diffrn_measurement_method       'φ scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0319
_diffrn_reflns_av_sigmaI/netI    0.0266
_diffrn_reflns_limit_h_max       4
_diffrn_reflns_limit_h_min       -4
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       7
_diffrn_reflns_limit_l_min       -7
_diffrn_reflns_number            1450
_diffrn_reflns_theta_full        27.98
_diffrn_reflns_theta_max         27.98
_diffrn_reflns_theta_min         4.04
_diffrn_standards_decay_%        none
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.131
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.594
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             116
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.185
_refine_diff_density_min         -0.144
_refine_ls_extinction_coef       0.41(9)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4^
_refine_ls_extinction_method     SHELXL97
_refine_ls_goodness_of_fit_ref   1.065
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     38
_refine_ls_number_reflns         551
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.065
_refine_ls_R_factor_all          0.0501
_refine_ls_R_factor_gt           0.0394
_refine_ls_shift/su_max          <0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[σ²(Fo²)+(0.0567P)²+0.0228P] where P = (Fo²+2Fc²)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0999
_refine_ls_wR_factor_ref         0.1058
_reflns_number_gt                427
_reflns_number_total             551
_reflns_threshold_expression     I>2σ(I)
_cod_data_source_file            bt6204.cif
_cod_data_source_block           I
_cod_original_cell_volume        233.48(6)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2201315
_cod_database_fobs_code          2201315
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'
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
N1 0.2159(3) 0.42985(10) 0.6583(2) 0.0419(4) Uani d . 1 . . N
O1 0.4230(3) 0.36378(9) 0.8052(2) 0.0578(4) Uani d . 1 . . O
C1 0.0743(4) 0.38407(12) 0.4468(2) 0.0454(4) Uani d . 1 . . C
H1 0.1242 0.3042 0.4082 0.054 Uiso calc R 1 . . H
C2 0.1397(4) 0.54639(12) 0.7094(2) 0.0445(4) Uani d . 1 . . C
H2 0.2348 0.5795 0.8531 0.053 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
N1 0.0458(6) 0.0394(6) 0.0381(6) -0.0046(4) -0.0045(5) 0.0035(4)
O1 0.0666(7) 0.0471(6) 0.0535(7) -0.0002(4) -0.0192(5) 0.0083(4)
C1 0.0517(8) 0.0383(6) 0.0440(8) -0.0027(5) -0.0033(6) -0.0039(5)
C2 0.0510(7) 0.0435(7) 0.0369(7) -0.0057(5) -0.0032(6) -0.0030(5)
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'
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_3
_geom_angle
_geom_angle_publ_flag
O1 N1 C2 . . 121.08(11) y
O1 N1 C1 . . 120.61(12) y
C2 N1 C1 . . 118.30(11) y
N1 C1 C2 . 3_566 120.83(13) y
N1 C1 H1 . . 119.6 n
C2 C1 H1 3_566 . 119.6 n
N1 C2 C1 . 3_566 120.87(12) y
N1 C2 H2 . . 119.6 n
C1 C2 H2 3_566 . 119.6 n
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 O1 . 1.2962(14) y
N1 C2 . 1.3526(17) y
N1 C1 . 1.3582(17) y
C1 C2 3_566 1.3617(19) y
C1 H1 . 0.9300 n
C2 C1 3_566 1.3617(19) n
C2 H2 . 0.9300 n
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
C1 H1 O1 4_565 0.93 2.27 3.1682(18) 162
C2 H2 O1 3_667 0.93 2.29 3.2067(19) 168
