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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         #
# reviewed under the auspices of the IUCr Commission on Journals.            #
#                                                                            #
# Full details of the Crystallographic Information File format               #
# 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 2.1.    #
#                                                                            #
# 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/  #
# cif/home.html                                                              #
#                                                                            #
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data_global
_audit_creation_method     'SHELXTL plus manual additions'
_journal_date_recd_electronic     2004-04-13
_journal_date_accepted     2004-06-08
_journal_name_full     'Acta Crystallographica, Section C'
_journal_year     2004
_journal_volume     60
_journal_issue      8
_journal_page_first     o552
_journal_page_last     o556
_journal_paper_category     FO
_publ_contact_author     'Doyle Britton'
_publ_contact_author_email     'britton@chem.umn.edu'
_publ_contact_author_fax     '612 626 7541'
_publ_contact_author_phone     '612 625 9535'
_publ_section_title
;
  p-Chloro-, p-bromo- and two polymorphs of p-iodoacetophenone
;
loop_
    _publ_author_name
    _publ_author_address
    'Britton, Doyle'
;
Department of Chemistry
University of Minnesota
Minneapolis, MN 55455-0431
USA
;
    'Brennessel, William W.'
;
Department of Chemistry
University of Minnesota
Minneapolis, MN 55455-0431
USA
;
_publ_section_synopsis
;
The packing in p-chloroacetophenone does not involve Cl...O
interactions.  In p-bromoacetophenone, Br...O contacts [3.320(4)
Å] are found.  In two polymorphs of p-iodooacetophenone, I...O
contacts [3.374(5) and 3.082(4) Å] are found.
;
data_ClM
_audit_creation_method     'SHELXTL plus manual additions'
_chemical_name_systematic
;
  4-chloroacetophenone
;
_chemical_name_common     ?
_chemical_formula_moiety     'C8 H7 Cl O'
_chemical_formula_sum     'C8 H7 Cl O'
_chemical_formula_weight     154.59
_chemical_melting_point     ?
_symmetry_cell_setting     orthorhombic
_symmetry_space_group_name_H-M     'P 21 21 21'
_symmetry_space_group_name_Hall     'P 2ac 2ab'
loop_
    _symmetry_equiv_pos_as_xyz
    'x, y, z'
    '-x+1/2, -y, z+1/2'
    '-x, y+1/2, -z+1/2'
    'x+1/2, -y+1/2, -z'
_cell_length_a     4.0079(10)
_cell_length_b     9.366(2)
_cell_length_c     19.787(5)
_cell_angle_alpha     90.00
_cell_angle_beta     90.00
_cell_angle_gamma     90.00
_cell_volume     742.8(3)
_cell_formula_units_Z     4
_cell_measurement_reflns_used     1949
_cell_measurement_theta_min     2.4
_cell_measurement_theta_max     25.6
_cell_measurement_temperature     173(2)
_exptl_crystal_description     'irregular prism'
_exptl_crystal_colour     colorless
_exptl_crystal_size_max     0.50
_exptl_crystal_size_mid     0.40
_exptl_crystal_size_min     0.30
_exptl_crystal_density_diffrn     1.382
_exptl_crystal_density_meas     'not measured'
_exptl_crystal_density_method     'not measured'
_exptl_crystal_F_000     320
_exptl_absorpt_coefficient_mu     0.435
_exptl_absorpt_correction_type     'multi-scan'
_exptl_absorpt_process_details
;
  SADABS; Sheldrick, 1996; Blessing, 1995
;
_exptl_absorpt_correction_T_min     0.81
_exptl_absorpt_correction_T_max     0.88
_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_type
;
  Siemens SMART area-detector diffractometer
;
_diffrn_measurement_method     'ω scans'
_diffrn_detector_area_resol_mean     ?
_diffrn_reflns_number     6382
_diffrn_reflns_av_R_equivalents     0.039
_diffrn_reflns_av_sigmaI/netI     0.043
_diffrn_reflns_theta_min     2.06
_diffrn_reflns_theta_max     27.54
_diffrn_reflns_theta_full     27.54
_diffrn_measured_fraction_theta_max     0.993
_diffrn_measured_fraction_theta_full     0.993
_diffrn_reflns_limit_h_min     -5
_diffrn_reflns_limit_h_max     5
_diffrn_reflns_limit_k_min     -12
_diffrn_reflns_limit_k_max     11
_diffrn_reflns_limit_l_min     -25
_diffrn_reflns_limit_l_max     23
_diffrn_standards_number     0
_diffrn_standards_interval_count     ?
_diffrn_standards_interval_time     ?
_diffrn_standards_decay_%     'less than 1'
_reflns_number_total     1674
_reflns_number_gt     1434
_reflns_threshold_expression     'I>2σ(I)'
_refine_ls_structure_factor_coef     Fsqd
_refine_ls_matrix_type     full
_refine_ls_R_factor_all     0.045
_refine_ls_R_factor_gt     0.034
_refine_ls_wR_factor_gt     0.076
_refine_ls_wR_factor_ref     0.080
_refine_ls_goodness_of_fit_ref     1.033
_refine_ls_restrained_S_all     1.033
_refine_ls_number_reflns     1674
_refine_ls_number_parameters     91
_refine_ls_number_restraints     0
_refine_ls_hydrogen_treatment     constr
_refine_ls_weighting_scheme     calc
_refine_ls_weighting_details
;
calc w=1/[σ²(Fo²)+(0.037P)²+0.061P] where
P=(Fo²+2Fc²)/3
;
_atom_sites_solution_hydrogens     geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary     difmap
_refine_ls_shift/su_max     0.002
_refine_ls_shift/su_mean     0.000
_refine_diff_density_max     0.17
_refine_diff_density_min     -0.14
_refine_ls_extinction_method     none
_refine_ls_extinction_coef     ?
_refine_ls_abs_structure_details     'Flack (1983)'
_refine_ls_abs_structure_Flack     0.11(8)
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'
    'O' 'O' 0.0106 0.0060
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
    'Cl' 'Cl' 0.1484 0.1585
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
_computing_data_collection     'SMART (Siemens, 1995)'
_computing_cell_refinement     'SAINT (Siemens, 1995)'
_computing_data_reduction     'SAINT'
_computing_structure_solution     'SHELXTL (Sheldrick, 1997)'
_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_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
    Cl1 0.66962(14) 0.52846(6) 0.44469(3) 0.04525(17) Uani d . 1 . . Cl
    O1 0.1053(4) 0.36413(15) 0.75213(8) 0.0476(4) Uani d . 1 . . O
    C1 0.3741(4) 0.48590(19) 0.66333(9) 0.0287(4) Uani d . 1 . . C
    C2 0.2919(5) 0.38008(18) 0.61662(9) 0.0318(4) Uani d . 1 . . C
    H2 0.1741 0.2976 0.6312 0.038 Uiso calc R 1 . . H
    C3 0.3790(5) 0.39346(19) 0.54971(10) 0.0337(4) Uani d . 1 . . C
    H3 0.3205 0.3213 0.5181 0.040 Uiso calc R 1 . . H
    C4 0.5526(4) 0.5132(2) 0.52905(10) 0.0311(4) Uani d . 1 . . C
    C5 0.6366(5) 0.62079(19) 0.57378(10) 0.0349(4) Uani d . 1 . . C
    H5 0.7531 0.7032 0.5587 0.042 Uiso calc R 1 . . H
    C6 0.5475(5) 0.60607(19) 0.64111(10) 0.0325(4) Uani d . 1 . . C
    H6 0.6052 0.6788 0.6725 0.039 Uiso calc R 1 . . H
    C7 0.2738(4) 0.4665(2) 0.73563(9) 0.0320(4) Uani d . 1 . . C
    C8 0.3818(5) 0.5757(2) 0.78664(10) 0.0414(5) Uani d . 1 . . C
    H8A 0.2998 0.5482 0.8315 0.062 Uiso calc R 1 . . H
    H8B 0.2901 0.6691 0.7743 0.062 Uiso calc R 1 . . H
    H8C 0.6259 0.5810 0.7874 0.062 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
    Cl1 0.0507(3) 0.0523(3) 0.0327(3) 0.0026(2) 0.0045(2) -0.0016(2)
    O1 0.0578(10) 0.0389(8) 0.0461(9) -0.0046(8) 0.0061(8) 0.0089(7)
    C1 0.0246(9) 0.0271(9) 0.0344(10) 0.0047(7) -0.0040(7) -0.0006(7)
    C2 0.0319(9) 0.0229(9) 0.0405(11) -0.0010(7) -0.0016(9) -0.0006(8)
    C3 0.0331(10) 0.0307(9) 0.0373(11) 0.0028(8) -0.0044(9) -0.0073(8)
    C4 0.0290(8) 0.0335(10) 0.0309(9) 0.0058(8) -0.0013(7) -0.0017(8)
    C5 0.0378(11) 0.0279(9) 0.0390(11) -0.0016(9) -0.0003(9) 0.0009(8)
    C6 0.0356(10) 0.0247(9) 0.0371(11) 0.0009(8) -0.0032(8) -0.0039(8)
    C7 0.0298(9) 0.0322(9) 0.0340(10) 0.0074(9) -0.0021(7) 0.0041(8)
    C8 0.0401(12) 0.0528(12) 0.0312(10) 0.0041(10) 0.0001(9) -0.0051(9)
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
    Cl1 C4 . 1.740(2) ?
    O1 C7 . 1.217(2) ?
    C1 C6 . 1.394(3) ?
    C1 C2 . 1.395(3) ?
    C1 C7 . 1.497(3) ?
    C2 C3 . 1.375(3) ?
    C2 H2 . 0.9500 ?
    C3 C4 . 1.382(3) ?
    C3 H3 . 0.9500 ?
    C4 C5 . 1.383(3) ?
    C5 C6 . 1.386(3) ?
    C5 H5 . 0.9500 ?
    C6 H6 . 0.9500 ?
    C7 C8 . 1.500(3) ?
    C8 H8A . 0.9800 ?
    C8 H8B . 0.9800 ?
    C8 H8C . 0.9800 ?
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
    C6 C1 C2 . . 118.86(17) ?
    C6 C1 C7 . . 122.22(17) ?
    C2 C1 C7 . . 118.93(16) ?
    C3 C2 C1 . . 120.89(17) ?
    C3 C2 H2 . . 119.6 ?
    C1 C2 H2 . . 119.6 ?
    C2 C3 C4 . . 119.13(17) ?
    C2 C3 H3 . . 120.4 ?
    C4 C3 H3 . . 120.4 ?
    C3 C4 C5 . . 121.65(18) ?
    C3 C4 Cl1 . . 119.12(15) ?
    C5 C4 Cl1 . . 119.24(15) ?
    C4 C5 C6 . . 118.67(17) ?
    C4 C5 H5 . . 120.7 ?
    C6 C5 H5 . . 120.7 ?
    C5 C6 C1 . . 120.79(17) ?
    C5 C6 H6 . . 119.6 ?
    C1 C6 H6 . . 119.6 ?
    O1 C7 C1 . . 120.05(17) ?
    O1 C7 C8 . . 121.07(18) ?
    C1 C7 C8 . . 118.87(17) ?
    C7 C8 H8A . . 109.5 ?
    C7 C8 H8B . . 109.5 ?
    H8A C8 H8B . . 109.5 ?
    C7 C8 H8C . . 109.5 ?
    H8A C8 H8C . . 109.5 ?
    H8B C8 H8C . . 109.5 ?
data_BrM
_audit_creation_method     'SHELXTL plus manual additions'
_chemical_name_systematic
;
  4-bromoacetophenone
;
_chemical_name_common     ?
_chemical_formula_moiety     ?
_chemical_formula_sum     'C8 H7 Br O'
_chemical_formula_weight     199.05
_chemical_melting_point     ?
_symmetry_cell_setting     monoclinic
_symmetry_space_group_name_H-M     'C c'
_symmetry_space_group_name_Hall     'C -2yc'
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'
_cell_length_a     18.635(5)
_cell_length_b     6.9554(17)
_cell_length_c     5.9035(15)
_cell_angle_alpha     90.00
_cell_angle_beta     96.360(10)
_cell_angle_gamma     90.00
_cell_volume     760.5(3)
_cell_formula_units_Z     4
_cell_measurement_reflns_used     2078
_cell_measurement_theta_min     2.2
_cell_measurement_theta_max     25.7
_cell_measurement_temperature     173(2)
_exptl_crystal_description     plate
_exptl_crystal_colour     colorless
_exptl_crystal_size_max     0.45
_exptl_crystal_size_mid     0.15
_exptl_crystal_size_min     0.03
_exptl_crystal_density_diffrn     1.739
_exptl_crystal_density_meas     'not measured '
_exptl_crystal_density_method     'not measured'
_exptl_crystal_F_000     392
_exptl_absorpt_coefficient_mu     5.328
_exptl_absorpt_correction_type     'multi-scan'
_exptl_absorpt_process_details
;
(SADABS including thin plate correction; Sheldrick, 1996; Blessing,
1995)
;
_exptl_absorpt_correction_T_min     0.39
_exptl_absorpt_correction_T_max     0.85
_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_type
;
Siemens SMART area-detector diffractometer
;
_diffrn_measurement_method     'ω scans'
_diffrn_detector_area_resol_mean     ?
_diffrn_reflns_number     3840
_diffrn_reflns_av_R_equivalents     0.038
_diffrn_reflns_av_sigmaI/netI     0.051
_diffrn_reflns_theta_min     3.13
_diffrn_reflns_theta_max     27.50
_diffrn_reflns_theta_full     27.50
_diffrn_measured_fraction_theta_max     0.993
_diffrn_measured_fraction_theta_full     0.993
_diffrn_reflns_limit_h_min     -23
_diffrn_reflns_limit_h_max     23
_diffrn_reflns_limit_k_min     -8
_diffrn_reflns_limit_k_max     9
_diffrn_reflns_limit_l_min     -7
_diffrn_reflns_limit_l_max     7
_diffrn_standards_number     0
_diffrn_standards_interval_count     ?
_diffrn_standards_interval_time     ?
_diffrn_standards_decay_%     ?
_reflns_number_total     1691
_reflns_number_gt     1569
_reflns_threshold_expression     'I>2σ(I)'
_refine_ls_structure_factor_coef     Fsqd
_refine_ls_matrix_type     full
_refine_ls_R_factor_all     0.037
_refine_ls_R_factor_gt     0.032
_refine_ls_wR_factor_gt     0.074
_refine_ls_wR_factor_ref     0.077
_refine_ls_goodness_of_fit_ref     1.05
_refine_ls_restrained_S_all     1.05
_refine_ls_number_reflns     1691
_refine_ls_number_parameters     91
_refine_ls_number_restraints     2
_refine_ls_hydrogen_treatment     constr
_refine_ls_weighting_scheme     calc
_refine_ls_weighting_details
;
calc w=1/[σ²(Fo²)+(0.036P)²] where
P=(Fo²+2Fc²)/3
;
_atom_sites_solution_hydrogens     geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary     difmap
_refine_ls_shift/su_max     0.001
_refine_ls_shift/su_mean     0.001
_refine_diff_density_max     0.75
_refine_diff_density_min     -0.27
_refine_ls_extinction_method     none
_refine_ls_extinction_coef     ?
_refine_ls_abs_structure_details
;
  Flack(1983),
  849 Friedel pairs
;
_refine_ls_abs_structure_Flack     -0.004(14)
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'
    '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, 1995)'
_computing_cell_refinement     'SAINT (Siemens, 1995)'
_computing_data_reduction     'SAINT'
_computing_structure_solution     'SHELXTL (Sheldrick, 1997)'
_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_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
    Br1 0.5000 0.27942(5) 0.5000 0.04028(13) Uani d . 1 . . Br
    O1 0.8276(2) 0.1930(5) 0.0907(6) 0.0486(8) Uani d . 1 . . O
    C1 0.7401(2) 0.2382(4) 0.3424(7) 0.0266(7) Uani d . 1 . . C
    C2 0.6834(2) 0.1785(6) 0.1811(7) 0.0284(9) Uani d . 1 . . C
    H2 0.6941 0.1297 0.0384 0.034 Uiso calc R 1 . . H
    C3 0.6124(2) 0.1895(5) 0.2261(6) 0.0292(8) Uani d . 1 . . C
    H3 0.5746 0.1480 0.1157 0.035 Uiso calc R 1 . . H
    C4 0.5969(2) 0.2617(5) 0.4340(7) 0.0282(8) Uani d . 1 . . C
    C5 0.6516(2) 0.3221(5) 0.5979(6) 0.0271(7) Uani d . 1 . . C
    H5 0.6402 0.3728 0.7390 0.033 Uiso calc R 1 . . H
    C6 0.7226(2) 0.3078(5) 0.5534(6) 0.0282(8) Uani d . 1 . . C
    H6 0.7602 0.3454 0.6668 0.034 Uiso calc R 1 . . H
    C7 0.8153(3) 0.2291(7) 0.2851(8) 0.0341(9) Uani d . 1 . . C
    C8 0.8756(3) 0.2688(6) 0.4701(9) 0.0439(10) Uani d . 1 . . C
    H8A 0.9221 0.2574 0.4079 0.066 Uiso calc R 1 . . H
    H8B 0.8737 0.1757 0.5938 0.066 Uiso calc R 1 . . H
    H8C 0.8705 0.3992 0.5291 0.066 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
    Br1 0.03165(19) 0.0465(2) 0.0438(2) 0.0034(4) 0.00901(13) 0.0015(5)
    O1 0.0398(19) 0.071(2) 0.0368(16) -0.0005(16) 0.0133(14) -0.0054(14)
    C1 0.036(2) 0.0173(16) 0.0269(16) -0.0001(12) 0.0042(15) 0.0007(12)
    C2 0.040(2) 0.023(2) 0.0228(18) 0.0000(17) 0.0047(14) 0.0003(15)
    C3 0.035(2) 0.026(2) 0.0261(17) -0.0029(14) -0.0015(14) -0.0036(12)
    C4 0.0271(19) 0.0241(18) 0.0342(19) 0.0020(13) 0.0074(15) 0.0050(13)
    C5 0.037(2) 0.0214(18) 0.0234(16) 0.0033(13) 0.0041(14) -0.0021(12)
    C6 0.037(2) 0.0221(19) 0.0257(18) -0.0018(13) 0.0031(15) -0.0010(12)
    C7 0.038(2) 0.030(2) 0.035(2) 0.002(2) 0.0076(18) 0.0011(19)
    C8 0.031(2) 0.056(3) 0.046(3) -0.0022(18) 0.0067(19) -0.0032(18)
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 C4 . 1.892(4) ?
    O1 C7 . 1.221(6) ?
    C1 C2 . 1.405(6) ?
    C1 C6 . 1.408(5) ?
    C1 C7 . 1.478(7) ?
    C2 C3 . 1.379(6) ?
    C2 H2 . 0.9500 ?
    C3 C4 . 1.386(6) ?
    C3 H3 . 0.9500 ?
    C4 C5 . 1.390(6) ?
    C5 C6 . 1.382(5) ?
    C5 H5 . 0.9500 ?
    C6 H6 . 0.9500 ?
    C7 C8 . 1.504(7) ?
    C8 H8A . 0.9800 ?
    C8 H8B . 0.9800 ?
    C8 H8C . 0.9800 ?
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
    C2 C1 C6 . . 118.1(4) ?
    C2 C1 C7 . . 119.6(4) ?
    C6 C1 C7 . . 122.4(4) ?
    C3 C2 C1 . . 121.3(4) ?
    C3 C2 H2 . . 119.4 ?
    C1 C2 H2 . . 119.4 ?
    C4 C3 C2 . . 119.3(4) ?
    C4 C3 H3 . . 120.3 ?
    C2 C3 H3 . . 120.3 ?
    C3 C4 C5 . . 121.1(4) ?
    C3 C4 Br1 . . 120.3(3) ?
    C5 C4 Br1 . . 118.7(3) ?
    C6 C5 C4 . . 119.4(3) ?
    C6 C5 H5 . . 120.3 ?
    C4 C5 H5 . . 120.3 ?
    C5 C6 C1 . . 120.9(4) ?
    C5 C6 H6 . . 119.5 ?
    C1 C6 H6 . . 119.5 ?
    O1 C7 C1 . . 120.4(4) ?
    O1 C7 C8 . . 121.1(5) ?
    C1 C7 C8 . . 118.5(4) ?
    C7 C8 H8A . . 109.5 ?
    C7 C8 H8B . . 109.5 ?
    H8A C8 H8B . . 109.5 ?
    C7 C8 H8C . . 109.5 ?
    H8A C8 H8C . . 109.5 ?
    H8B C8 H8C . . 109.5 ?
data_IM-A
_audit_creation_method     'SHELXTL plus manual additions'
_chemical_name_systematic
;
  p-iodoacetophenone polymorph A
;
_chemical_name_common     ?
_chemical_formula_moiety     'C8 H7 I O'
_chemical_formula_sum     'C8 H7 I O'
_chemical_formula_weight     246.04
_chemical_melting_point     '358-359 K'
_symmetry_cell_setting     monoclinic
_symmetry_space_group_name_H-M     'C c'
_symmetry_space_group_name_Hall     'C -2yc'
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'
_cell_length_a     19.425(5)
_cell_length_b     7.049(2)
_cell_length_c     5.8769(15)
_cell_angle_alpha     90.00
_cell_angle_beta     94.410(10)
_cell_angle_gamma     90.00
_cell_volume     802.3(4)
_cell_formula_units_Z     4
_cell_measurement_reflns_used     3302
_cell_measurement_theta_min     3.1
_cell_measurement_theta_max     27.5
_cell_measurement_temperature     173(2)
_exptl_crystal_description     plate
_exptl_crystal_colour     'pale yellow'
_exptl_crystal_size_max     0.25
_exptl_crystal_size_mid     0.20
_exptl_crystal_size_min     0.10
_exptl_crystal_density_diffrn     2.037
_exptl_crystal_density_meas     'not measured'
_exptl_crystal_density_method     'not measured'
_exptl_crystal_F_000     464
_exptl_absorpt_coefficient_mu     3.918
_exptl_absorpt_correction_type     'multi-scan'
_exptl_absorpt_process_details
;
(SADABS; Sheldrick, 1996; Blessing, 1995)
;
_exptl_absorpt_correction_T_min     0.38
_exptl_absorpt_correction_T_max     0.68
_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_type
;
Siemens SMART area-detector diffractometer
;
_diffrn_measurement_method     'ω scans'
_diffrn_detector_area_resol_mean     ?
_diffrn_reflns_number     4483
_diffrn_reflns_av_R_equivalents     0.031
_diffrn_reflns_av_sigmaI/netI     0.037
_diffrn_reflns_theta_min     2.10
_diffrn_reflns_theta_max     27.50
_diffrn_reflns_theta_full     27.50
_diffrn_measured_fraction_theta_max     0.998
_diffrn_measured_fraction_theta_full     0.998
_diffrn_reflns_limit_h_min     -25
_diffrn_reflns_limit_h_max     25
_diffrn_reflns_limit_k_min     -9
_diffrn_reflns_limit_k_max     9
_diffrn_reflns_limit_l_min     -7
_diffrn_reflns_limit_l_max     7
_diffrn_standards_number     0
_diffrn_standards_interval_count     ?
_diffrn_standards_interval_time     ?
_diffrn_standards_decay_%     ' less than 1 '
_reflns_number_total     1821
_reflns_number_gt     1768
_reflns_threshold_expression     'I>2σ(I) '
_refine_ls_structure_factor_coef     Fsqd
_refine_ls_matrix_type     full
_refine_ls_R_factor_all     0.024
_refine_ls_R_factor_gt     0.023
_refine_ls_wR_factor_gt     0.059
_refine_ls_wR_factor_ref     0.060
_refine_ls_goodness_of_fit_ref     1.05
_refine_ls_restrained_S_all     1.05
_refine_ls_number_reflns     1821
_refine_ls_number_parameters     91
_refine_ls_number_restraints     2
_refine_ls_hydrogen_treatment     constr
_refine_ls_weighting_scheme     calc
_refine_ls_weighting_details
;
calc w=1/[σ²(Fo²)+(0.032P)²+0.031P] where
P=(Fo²+2Fc²)/3
;
_atom_sites_solution_hydrogens     geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary     difmap
_refine_ls_shift/su_max     0.001
_refine_ls_shift/su_mean     0.000
_refine_diff_density_max     0.63
_refine_diff_density_min     -0.31
_refine_ls_extinction_method     none
_refine_ls_extinction_coef     ?
_refine_ls_abs_structure_details     'Flack (1983)'
_refine_ls_abs_structure_Flack     -0.01(3)
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'
    'O' 'O' 0.0106 0.0060
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
    'I' 'I' -0.4742 1.8119
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
_computing_data_collection     'SMART (Siemens, 1995)'
_computing_cell_refinement     'SAINT (Siemens, 1995)'
_computing_data_reduction     'SAINT'
_computing_structure_solution     'SHELXTL (Sheldrick, 1997)'
_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_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
    I1 0.5000 0.26811(3) 0.5000 0.03998(9) Uani d . 1 . . I
    O1 0.8311(2) 0.2031(5) 0.0940(7) 0.0532(8) Uani d . 1 . . O
    C1 0.7426(2) 0.2402(4) 0.3415(7) 0.0278(7) Uani d . 1 . . C
    C2 0.6910(2) 0.1829(6) 0.1788(7) 0.0297(8) Uani d . 1 . . C
    H2 0.7034 0.1383 0.0351 0.036 Uiso calc R 1 . . H
    C3 0.6220(2) 0.1895(5) 0.2210(6) 0.0307(6) Uani d . 1 . . C
    H3 0.5876 0.1475 0.1088 0.037 Uiso calc R 1 . . H
    C4 0.6037(2) 0.2580(4) 0.4291(7) 0.0285(8) Uani d . 1 . . C
    C5 0.6537(2) 0.3188(5) 0.5961(6) 0.0300(6) Uani d . 1 . . C
    H5 0.6405 0.3664 0.7376 0.036 Uiso calc R 1 . . H
    C6 0.7228(2) 0.3088(5) 0.5534(6) 0.0303(6) Uani d . 1 . . C
    H6 0.7572 0.3484 0.6673 0.036 Uiso calc R 1 . . H
    C7 0.8164(3) 0.2347(6) 0.2888(9) 0.0337(9) Uani d . 1 . . C
    C8 0.8714(3) 0.2684(6) 0.4777(10) 0.0475(11) Uani d . 1 . . C
    H8A 0.9169 0.2613 0.4169 0.071 Uiso calc R 1 . . H
    H8B 0.8681 0.1716 0.5960 0.071 Uiso calc R 1 . . H
    H8C 0.8651 0.3944 0.5436 0.071 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
    I1 0.03069(13) 0.04697(13) 0.04280(14) 0.0027(3) 0.00627(9) 0.0040(3)
    O1 0.0398(19) 0.083(2) 0.0382(16) -0.0006(17) 0.0135(14) -0.0091(16)
    C1 0.032(2) 0.0273(15) 0.0250(16) 0.0004(11) 0.0064(14) 0.0007(10)
    C2 0.0402(19) 0.0263(18) 0.0228(16) 0.0007(16) 0.0034(13) -0.0010(14)
    C3 0.0349(18) 0.0292(15) 0.0272(15) -0.0011(14) -0.0025(13) -0.0034(12)
    C4 0.030(2) 0.0259(15) 0.0300(19) 0.0006(11) 0.0023(16) 0.0040(10)
    C5 0.0403(18) 0.0267(14) 0.0230(14) 0.0008(13) 0.0030(12) -0.0007(11)
    C6 0.0367(17) 0.0278(15) 0.0261(15) -0.0025(13) 0.0013(12) -0.0033(12)
    C7 0.034(2) 0.029(2) 0.038(2) 0.0011(16) 0.0074(18) 0.0002(15)
    C8 0.033(2) 0.068(3) 0.042(3) -0.0055(17) 0.0051(19) -0.0008(17)
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
    I1 C4 . 2.090(5) ?
    O1 C7 . 1.221(7) ?
    C1 C2 . 1.391(6) ?
    C1 C6 . 1.416(5) ?
    C1 C7 . 1.491(7) ?
    C2 C3 . 1.381(6) ?
    C2 H2 . 0.9500 ?
    C3 C4 . 1.387(6) ?
    C3 H3 . 0.9500 ?
    C4 C5 . 1.393(6) ?
    C5 C6 . 1.387(5) ?
    C5 H5 . 0.9500 ?
    C6 H6 . 0.9500 ?
    C7 C8 . 1.499(8) ?
    C8 H8A . 0.9800 ?
    C8 H8B . 0.9800 ?
    C8 H8C . 0.9800 ?
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
    C2 C1 C6 . . 118.3(4) ?
    C2 C1 C7 . . 120.2(4) ?
    C6 C1 C7 . . 121.5(4) ?
    C3 C2 C1 . . 121.6(4) ?
    C3 C2 H2 . . 119.2 ?
    C1 C2 H2 . . 119.2 ?
    C4 C3 C2 . . 119.2(4) ?
    C4 C3 H3 . . 120.4 ?
    C2 C3 H3 . . 120.4 ?
    C3 C4 C5 . . 121.1(4) ?
    C3 C4 I1 . . 120.3(3) ?
    C5 C4 I1 . . 118.6(3) ?
    C6 C5 C4 . . 119.3(3) ?
    C6 C5 H5 . . 120.4 ?
    C4 C5 H5 . . 120.4 ?
    C5 C6 C1 . . 120.5(3) ?
    C5 C6 H6 . . 119.7 ?
    C1 C6 H6 . . 119.7 ?
    O1 C7 C1 . . 119.8(5) ?
    O1 C7 C8 . . 121.2(5) ?
    C1 C7 C8 . . 118.9(5) ?
    C7 C8 H8A . . 109.5 ?
    C7 C8 H8B . . 109.5 ?
    H8A C8 H8B . . 109.5 ?
    C7 C8 H8C . . 109.5 ?
    H8A C8 H8C . . 109.5 ?
    H8B C8 H8C . . 109.5 ?
data_IM-B
_audit_creation_method     ' SHELXTL plus manual additions'
_chemical_name_systematic
;
  p-iodoacetophenone  polymorph B
;
_chemical_name_common     ?
_chemical_formula_moiety     'C8 H7 I O'
_chemical_formula_sum     'C8 H7 I O'
_chemical_formula_weight     246.04
_chemical_melting_point     '357-359 K'
_symmetry_cell_setting     orthorhombic
_symmetry_space_group_name_H-M     'P b c a'
_symmetry_space_group_name_Hall     '-P 2ac 2ab'
loop_
    _symmetry_equiv_pos_as_xyz
    'x, y, z'
    '-x+1/2, -y, z+1/2'
    '-x, y+1/2, -z+1/2'
    'x+1/2, -y+1/2, -z'
    '-x, -y, -z'
    'x-1/2, y, -z-1/2'
    'x, -y-1/2, z-1/2'
    '-x-1/2, y-1/2, z'
_cell_length_a     9.777(2)
_cell_length_b     8.232(2)
_cell_length_c     20.089(5)
_cell_angle_alpha     90.00
_cell_angle_beta     90.00
_cell_angle_gamma     90.00
_cell_volume     1616.8(7)
_cell_formula_units_Z     8
_cell_measurement_reflns_used     2276
_cell_measurement_theta_min     2.9
_cell_measurement_theta_max     27.4
_cell_measurement_temperature     173(2)
_exptl_crystal_description     plate
_exptl_crystal_colour     colorless
_exptl_crystal_size_max     0.25
_exptl_crystal_size_mid     0.20
_exptl_crystal_size_min     0.01
_exptl_crystal_density_diffrn     2.021
_exptl_crystal_density_meas     'not measured'
_exptl_crystal_density_method     'not measured'
_exptl_crystal_F_000     928
_exptl_absorpt_coefficient_mu     3.888
_exptl_absorpt_correction_type     'multi-scan '
_exptl_absorpt_process_details
;
SADABS; Sheldrick, 1996; Blessing, 1995
;
_exptl_absorpt_correction_T_min     0.41
_exptl_absorpt_correction_T_max     0.96
_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_type
;
Siemans SMART area-detector diffractometer
;
_diffrn_measurement_method     'ω scans'
_diffrn_detector_area_resol_mean     ?
_diffrn_reflns_number     15576
_diffrn_reflns_av_R_equivalents     0.052
_diffrn_reflns_av_sigmaI/netI     0.031
_diffrn_reflns_theta_min     2.91
_diffrn_reflns_theta_max     27.50
_diffrn_reflns_theta_full     27.50
_diffrn_measured_fraction_theta_max     0.998
_diffrn_measured_fraction_theta_full     0.998
_diffrn_reflns_limit_h_min     -12
_diffrn_reflns_limit_h_max     12
_diffrn_reflns_limit_k_min     -10
_diffrn_reflns_limit_k_max     10
_diffrn_reflns_limit_l_min     -26
_diffrn_reflns_limit_l_max     26
_diffrn_standards_number     0
_diffrn_standards_interval_count     ?
_diffrn_standards_interval_time     ?
_diffrn_standards_decay_%     ?
_reflns_number_total     1855
_reflns_number_gt     1236
_reflns_threshold_expression     'I>2σ(I) '
_refine_ls_structure_factor_coef     Fsqd
_refine_ls_matrix_type     full
_refine_ls_R_factor_all     0.049
_refine_ls_R_factor_gt     0.026
_refine_ls_wR_factor_gt     0.059
_refine_ls_wR_factor_ref     0.070
_refine_ls_goodness_of_fit_ref     1.09
_refine_ls_restrained_S_all     1.09
_refine_ls_number_reflns     1855
_refine_ls_number_parameters     91
_refine_ls_number_restraints     0
_refine_ls_hydrogen_treatment     constr
_refine_ls_weighting_scheme     calc
_refine_ls_weighting_details
;
  calc w=1/[σ²(Fo²)+(0.019P)²+2.68P] where
P=(Fo²+2Fc²)/3
;
_atom_sites_solution_hydrogens     geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary     difmap
_refine_ls_shift/su_max     0.002
_refine_ls_shift/su_mean     0.000
_refine_diff_density_max     0.56
_refine_diff_density_min     -0.45
_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'
    'O' 'O' 0.0106 0.0060
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
    'I' 'I' -0.4742 1.8119
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
_computing_data_collection     'SMART (Siemens, 1995)'
_computing_cell_refinement     'SAINT (Siemens, 1995)'
_computing_data_reduction     'SAINT'
_computing_structure_solution     'SHELXTL (Sheldrick, 1997)'
_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_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
    I1 0.58879(2) 0.25265(3) 0.657830(12) 0.03254(10) Uani d . 1 . . I
    O1 0.5437(3) 0.1968(4) 1.00741(14) 0.0375(6) Uani d . 1 . . O
    C1 0.6182(4) 0.1533(4) 0.89715(18) 0.0258(8) Uani d . 1 . . C
    C2 0.5141(4) 0.2487(4) 0.87084(19) 0.0299(7) Uani d . 1 . . C
    H2 0.4479 0.2949 0.8998 0.036 Uiso calc R 1 . . H
    C3 0.5053(4) 0.2772(4) 0.8031(2) 0.0307(9) Uani d . 1 . . C
    H3 0.4343 0.3436 0.7856 0.037 Uiso calc R 1 . . H
    C4 0.6014(4) 0.2080(4) 0.76080(19) 0.0278(8) Uani d . 1 . . C
    C5 0.7058(4) 0.1120(4) 0.78602(19) 0.0294(8) Uani d . 1 . . C
    H5 0.7715 0.0650 0.7570 0.035 Uiso calc R 1 . . H
    C6 0.7133(4) 0.0854(5) 0.85411(19) 0.0297(8) Uani d . 1 . . C
    H6 0.7847 0.0196 0.8715 0.036 Uiso calc R 1 . . H
    C7 0.6249(4) 0.1289(4) 0.97091(19) 0.0291(8) Uani d . 1 . . C
    C8 0.7347(4) 0.0212(5) 0.9984(2) 0.0427(10) Uani d . 1 . . C
    H8A 0.7272 0.0174 1.0470 0.064 Uiso calc R 1 . . H
    H8B 0.8245 0.0643 0.9859 0.064 Uiso calc R 1 . . H
    H8C 0.7241 -0.0886 0.9803 0.064 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
    I1 0.03458(15) 0.03895(16) 0.02411(15) -0.00124(12) 0.00010(9) 0.00237(12)
    O1 0.0456(16) 0.0407(14) 0.0263(15) 0.0027(13) 0.0019(13) -0.0030(12)
    C1 0.0259(18) 0.0242(18) 0.027(2) -0.0038(14) 0.0000(15) 0.0006(15)
    C2 0.0316(18) 0.0314(18) 0.0268(19) 0.0031(18) -0.0001(15) -0.0043(18)
    C3 0.0293(18) 0.032(2) 0.031(2) 0.0069(15) -0.0040(15) 0.0007(16)
    C4 0.0325(19) 0.0270(18) 0.024(2) -0.0057(15) -0.0025(15) -0.0017(14)
    C5 0.0236(18) 0.0341(19) 0.030(2) 0.0018(15) 0.0058(15) -0.0007(17)
    C6 0.0282(19) 0.032(2) 0.029(2) 0.0031(16) -0.0015(15) 0.0040(16)
    C7 0.0344(19) 0.0275(18) 0.025(2) -0.0066(15) -0.0029(17) 0.0009(16)
    C8 0.046(3) 0.048(3) 0.034(2) 0.007(2) -0.002(2) 0.0043(19)
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
    I1 C4 . 2.105(4) ?
    O1 C7 . 1.217(5) ?
    C1 C6 . 1.387(5) ?
    C1 C2 . 1.390(5) ?
    C1 C7 . 1.497(5) ?
    C2 C3 . 1.384(6) ?
    C2 H2 . 0.9500 ?
    C3 C4 . 1.389(5) ?
    C3 H3 . 0.9500 ?
    C4 C5 . 1.387(5) ?
    C5 C6 . 1.387(5) ?
    C5 H5 . 0.9500 ?
    C6 H6 . 0.9500 ?
    C7 C8 . 1.497(5) ?
    C8 H8A . 0.9800 ?
    C8 H8B . 0.9800 ?
    C8 H8C . 0.9800 ?
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
    C6 C1 C2 . . 118.8(3) ?
    C6 C1 C7 . . 122.2(3) ?
    C2 C1 C7 . . 119.0(3) ?
    C3 C2 C1 . . 121.0(3) ?
    C3 C2 H2 . . 119.5 ?
    C1 C2 H2 . . 119.5 ?
    C2 C3 C4 . . 119.3(3) ?
    C2 C3 H3 . . 120.3 ?
    C4 C3 H3 . . 120.3 ?
    C5 C4 C3 . . 120.6(4) ?
    C5 C4 I1 . . 120.1(3) ?
    C3 C4 I1 . . 119.3(3) ?
    C6 C5 C4 . . 119.3(3) ?
    C6 C5 H5 . . 120.4 ?
    C4 C5 H5 . . 120.4 ?
    C5 C6 C1 . . 121.0(3) ?
    C5 C6 H6 . . 119.5 ?
    C1 C6 H6 . . 119.5 ?
    O1 C7 C1 . . 120.4(3) ?
    O1 C7 C8 . . 121.1(4) ?
    C1 C7 C8 . . 118.4(3) ?
    C7 C8 H8A . . 109.5 ?
    C7 C8 H8B . . 109.5 ?
    H8A C8 H8B . . 109.5 ?
    C7 C8 H8C . . 109.5 ?
    H8A C8 H8C . . 109.5 ?
    H8B C8 H8C . . 109.5 ?
