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###           Full Paper (Acta Crystallographica Section C)                ###
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#                                                                            #
# This CIF contains the data in a paper accepted for publication in Acta     #
# Crystallographica Section C. It conforms to the editorial and technical    #
# requirements of Notes for Authors for Section C, and has been peer         #
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# are given in the paper "The Crystallographic Information File (CIF):       #
# a New Standard Archive File for Crystallography" by S. R. Hall, F. H.      #
# Allen and I. D. Brown [Acta Cryst. (1991), A47, 655-685].                  #
#                                                                            #
# The current version of the core CIF dictionary is obtainable from          #
# ftp://ftp.iucr.org/pub/cif_core.dic. The current version number is 2.0.1.  #
#                                                                            #
# Software is freely available for graphical display of the structure(s) in  #
# this CIF.  For information consult the CIF home page http://www.iucr.org/  #
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#                                                                            #
# This file may be used for bona fide research purposes within the           #
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data_global
_journal_date_recd_electronic     97-10-28
_journal_date_accepted     98-01-29
_journal_name_full     'Acta Crystallographica, Section C'
_journal_year     1998
_journal_volume     C54
_journal_issue     AUG98
_journal_page_first     1113
_journal_page_last     1115
_journal_paper_category     FO
_publ_contact_author_name     'Prof A. Guy Orpen'
_publ_contact_author_address
;
School of Chemistry
Cantocks Close
University of Bristol
Bristol
BS8 1TS
;
_publ_contact_author_email     guy.orpen@bris.ac.uk
_publ_contact_author_fax     '0117 929 0509'
_publ_contact_author_phone     '0117 928 7648'
_publ_section_title
;
2,6-Dibromo-4-nitroaniline
;
loop_
    _publ_author_name
    _publ_author_address
    'Bryant, Richard'
;  School of Chemistry
 University of Bristol
 Cantocks Close
 Bristol BS8 1TS, England
;
    'James, Siân C.'
;  School of Chemistry
 University of Bristol
 Cantocks Close
 Bristol BS8 1TS, England
;
    'Norman, Nicholas C.'
;  School of Chemistry
 University of Bristol
 Cantocks Close
 Bristol BS8 1TS, England
;
    'Orpen, A. Guy'
;  School of Chemistry
 University of Bristol
 Cantocks Close
 Bristol BS8 1TS, England
;
data_ha1207
_chemical_name_systematic
;
2,6-dibromo-4-nitroaniline
;
_chemical_name_common     2,6-dibromo-4-nitroaniline
_chemical_formula_moiety     'C6 H4 Br2 N2 O2'
_chemical_formula_sum     'C6 H4 Br2 N2 O2'
_chemical_formula_structural     ?
_chemical_formula_analytical     ?
_chemical_formula_weight     295.918
_chemical_melting_point     ?
_symmetry_cell_setting     monoclinic
_symmetry_space_group_name_H-M     'P 21/m'
_symmetry_space_group_name_Hall     '-P 2y1'
loop_
    _symmetry_equiv_pos_as_xyz
    'x, y, z'
    '-x, y+1/2, -z'
    '-x, -y, -z'
    'x, -y-1/2, z'
_cell_length_a     4.2308(3)
_cell_length_b     14.2071(9)
_cell_length_c     7.0308(5)
_cell_angle_alpha     90.00
_cell_angle_beta     101.9610(10)
_cell_angle_gamma     90.00
_cell_volume     413.43(5)
_cell_formula_units_Z     2
_cell_measurement_reflns_used     65
_cell_measurement_theta_min     5
_cell_measurement_theta_max     50
_cell_measurement_temperature     173(2)
_exptl_crystal_description     block
_exptl_crystal_colour     'dark red'
_exptl_crystal_size_max     0.5
_exptl_crystal_size_mid     0.4
_exptl_crystal_size_min     0.2
_exptl_crystal_density_diffrn     2.3771
_exptl_crystal_density_meas     'Not measured'
_exptl_crystal_density_method     'Not measured'
_exptl_crystal_F_000     280
_exptl_absorpt_coefficient_mu     9.760
_exptl_absorpt_correction_type     'SADABS (Sheldrick, 1996)'
_exptl_absorpt_correction_T_min     0.247
_exptl_absorpt_correction_T_max     0.746
_exptl_special_details
; ?
;
_diffrn_ambient_temperature     173(2)
_diffrn_radiation_type     MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_radiation_source     'fine-focus sealed tube'
_diffrn_radiation_monochromator     graphite
_diffrn_measurement_device     'Siemens CCD area-detector'
_diffrn_measurement_method     'ω rotation with narrow frame'
_diffrn_detector_area_resol_mean     60
_diffrn_reflns_number     2673
_diffrn_reflns_av_R_equivalents     0.0498
_diffrn_reflns_av_sigmaI/netI     0.0653
_diffrn_reflns_theta_min     2.87
_diffrn_reflns_theta_max     27.48
_diffrn_reflns_theta_full     46.51
_diffrn_measured_fraction_theta_max     99.1
_diffrn_reflns_limit_h_min     -5
_diffrn_reflns_limit_h_max     5
_diffrn_reflns_limit_k_min     -9
_diffrn_reflns_limit_k_max     18
_diffrn_reflns_limit_l_min     -8
_diffrn_reflns_limit_l_max     9
_diffrn_standards_number     ?
_diffrn_standards_interval_count     ?
_diffrn_standards_interval_time     ?
_diffrn_standards_decay_%     'none'
_reflns_number_total     989
_reflns_number_observed     739
_reflns_observed_criterion     >2sigma(I)
_refine_ls_structure_factor_coef     Fsqd
_refine_ls_matrix_type     full
_refine_ls_R_factor_all     0.0666
_refine_ls_R_factor_obs     0.0588
_refine_ls_wR_factor_all     0.1477
_refine_ls_wR_factor_obs     0.1459
_refine_ls_goodness_of_fit_all     0.994
_refine_ls_goodness_of_fit_obs     1.145
_refine_ls_restrained_S_all     0.994
_refine_ls_restrained_S_obs     1.145
_refine_ls_number_reflns     989
_refine_ls_number_parameters     61
_refine_ls_number_restraints     0
_refine_ls_hydrogen_treatment     'H atoms: see texxt below'
_refine_ls_weighting_scheme
               'calc w = 1/[\s^2^(Fo^2^)+(0.0924P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_shift/esd_max     0.001
_refine_ls_shift/esd_mean     0.000
_refine_diff_density_max     2.097_(0.9\%A_from_Br1)
_refine_diff_density_min     -1.474_(1.34\%A_from_Br1)
_refine_ls_extinction_method     none
_refine_ls_extinction_coef     ?
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'
    'Br' 'Br' -0.2901 2.4595
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
_computing_data_collection     'SMART (Siemens, 1995a)'
_computing_cell_refinement     'SAINT (Siemens, 1995a)'
_computing_data_reduction     'SAINT'
_computing_structure_solution     'SHELXTL (Siemens, 1995b)'
_computing_structure_refinement     'SHELXTL'
_computing_molecular_graphics     'SHELXTL'
_computing_publication_material     'SHELXTL'
loop_
    _atom_site_label
    _atom_site_fract_x
    _atom_site_fract_y
    _atom_site_fract_z
    _atom_site_U_iso_or_equiv
    _atom_site_thermal_displace_type
    _atom_site_calc_flag
    _atom_site_refinement_flags
    _atom_site_occupancy
    _atom_site_disorder_group
    _atom_site_type_symbol
    Br1 0.1856(2) 0.54968(5) 0.26456(11) 0.0262(3) Uani d . 1 . Br
    C1 0.189(2)   0.7500 0.2366(13) 0.016(2) Uani d S 1 . C
    C2 0.2704(15) 0.6658(4) 0.1537(11) 0.0179(14) Uani d . 1 . C
    C3 0.4140(14) 0.6645(4) -0.0061(10) 0.0186(14) Uani d . 1 . C
    H3A 0.4627(14) 0.6067(4) -0.0616(10) 0.022 Uiso calc R 1 . H
    C4 0.485(2)   0.7500 -0.0831(14) 0.017(2) Uani d S 1 . C
    N1 0.0470(19) 0.7500 0.3914(12) 0.022(2) Uani d S 1 . N
    H1A 0.0029(19) 0.8036 0.4428(12) 0.026 Uiso calc PR 0.50 . H
    H1B -0.0017(19) 0.6964 0.4409(12) 0.026 Uiso calc PR 0.50 . H
    N2 0.6415(18) 0.7500 -0.2488(12) 0.019(2) Uani d S 1 . N
    O1 0.7047(12) 0.6738(4) -0.3164(8) 0.0262(11) Uani d . 1 . O
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
    Br1 0.0363(5) 0.0197(4) 0.0246(5) -0.0027(3) 0.0107(3) 0.0047(3)
    C1 0.012(4) 0.021(5) 0.011(5) 0.000 -0.003(3) 0.000
    C2 0.020(3) 0.016(3) 0.019(4) -0.004(2) 0.004(3) -0.001(3)
    C3 0.017(3) 0.019(3) 0.019(4) 0.001(2) 0.002(3) 0.002(3)
    C4 0.014(4) 0.024(5) 0.014(5) 0.000 0.007(3) 0.000
    N1 0.030(4) 0.021(4) 0.015(4) 0.000 0.007(3) 0.000
    N2 0.024(4) 0.022(4) 0.014(4) 0.000 0.008(3) 0.000
    O1 0.038(3) 0.023(3) 0.021(3) 0.000(2) 0.013(2) -0.005(2)
_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_site_symmetry_2
    _geom_bond_distance
    _geom_bond_publ_flag
    Br1 C2 . 1.890(7) yes
    C1 N1 . 1.349(12) yes
    C1 C2 4_575 1.404(8) yes
    C1 C2 . 1.404(8) yes
    C2 C3 . 1.384(10) yes
    C3 C4 . 1.388(8) yes
    C4 C3 4_575 1.388(8) yes
    C4 N2 . 1.455(12) yes
    N1 O1 4_476 2.941(9) yes
    N1 O1 1_456 2.941(9) yes
    N2 O1 4_575 1.234(6) yes
    N2 O1 . 1.234(6) yes
    O1 H1A 4_674 2.334(9) yes
    O1 Br1 3_665 3.218(5) yes
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
    N1 C1 C2 . 4_575 121.6(4) yes
    N1 C1 C2 . . 121.6(4) yes
    C2 C1 C2 4_575 . 116.9(8) yes
    C3 C2 C1 . . 122.3(6) yes
    C3 C2 Br1 . . 118.4(5) yes
    C1 C2 Br1 . . 119.3(5) yes
    C2 C3 C4 . . 118.1(6) yes
    C3 C4 C3 4_575 . 122.2(9) yes
    C3 C4 N2 4_575 . 118.9(5) yes
    C3 C4 N2 . . 118.9(5) yes
    C1 N1 O1 . 4_476 157.9(2) yes
    C1 N1 O1 . 1_456 157.9(2) yes
    O1 N1 O1 4_476 1_456 43.1(2) yes
    O1 N2 O1 4_575 . 122.7(8) yes
    O1 N2 C4 4_575 . 118.6(4) yes
    O1 N2 C4 . . 118.6(4) yes
    N2 O1 H1A . 4_674 110.6(5) yes
    N2 O1 Br1 . 3_665 149.3(5) yes
    H1A O1 Br1 4_674 3_665 97.5(2) yes
