Crystal engineering in the <i>gem</i>-alkynol family: interplay between strong and weak interactions in structures of 2,3,5,6-tetrahalo[F,Cl,Br]-<i>trans</i>-1,4-diethynylcyclohexa-2,5-diene-1,4-diols
Madhavi, N. N. L.; Desiraju, Gautam R.; Bilton, Claire; Howard, Judith A. K.; Allen, Frank H.; Acta Crystallographica Section B 56 (2000) 1063–1070; doi:10.1107/S0108768100011496

data_2102176
_publ_section_title
;Crystal engineering in the <i>gem</i>-alkynol family: interplay between
 strong and weak interactions in structures of
 2,3,5,6-tetrahalo[F,Cl,Br]-<i>trans</i>-1,4-diethynylcyclohexa-2,5-diene-1,4-diols
;
_journal_coeditor_code           BM0033
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              1063
_journal_page_last               1070
_journal_paper_doi               10.1107/S0108768100011496
_journal_volume                  56
_journal_year                    2000
_chemical_formula_moiety         'C10 H4 Cl4 O2'
_chemical_formula_sum            'C10 H4 Cl4 O2'
_chemical_formula_weight         297.93
_chemical_melting_point          205.5(5)
_chemical_name_systematic
'  2,3,5,6-tetrachloro-trans-1,4-diethynyl-cyclohexa-2,5-diene-1,4-diol'
_space_group_IT_number           88
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  '-I 4ad'
_symmetry_space_group_name_H-M   'I 41/a :2'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   16.758(2)
_cell_length_b                   16.758(2)
_cell_length_c                   8.865(2)
_cell_measurement_reflns_used    505
_cell_measurement_temperature    150
_cell_measurement_theta_max      25.31
_cell_measurement_theta_min      5.26
_cell_volume                     2489.6(7)
_computing_cell_refinement       'Bruker SMART (Bruker Systems Inc., 1999a)'
_computing_data_collection       'Bruker SMART (Bruker Systems Inc., 1999a)'
_computing_data_reduction        'Bruker SAINT (Bruker Systems Inc., 1999b)'
_computing_molecular_graphics    'SHELXL97 (Sheldrick, 1997)'
_computing_publication_material  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      150
_diffrn_detector_area_resol_mean 'not relevant'
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker SMART CCD'
_diffrn_measurement_method       \w
_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  0.0432
_diffrn_reflns_av_sigmaI/netI    0.0245
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -21
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -9
_diffrn_reflns_number            8404
_diffrn_reflns_theta_full        27.39
_diffrn_reflns_theta_max         27.39
_diffrn_reflns_theta_min         2.43
_exptl_absorpt_coefficient_mu    0.930
_exptl_absorpt_correction_T_max  0.830
_exptl_absorpt_correction_T_min  0.665
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Sheldrick 1996)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.590
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1184
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.3
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.589
_refine_diff_density_min         -0.437
_refine_diff_density_rms         0.055
_refine_ls_extinction_coef       0.0178(11)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.091
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     82
_refine_ls_number_reflns         1421
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.091
_refine_ls_R_factor_all          0.0590
_refine_ls_R_factor_gt           0.0489
_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/[\s^2^(Fo^2^)+(0.0383P)^2^+5.8833P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1160
_refine_ls_wR_factor_ref         0.1245
_reflns_number_gt                1202
_reflns_number_total             1421
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            bm0033.cif
_cod_data_source_block           8
_cod_depositor_comments
;
The following automatic conversions were performed:

'_chemical_melting_point' value '205-206' was changed to '205.5(5)' -
the average value was taken and precision was estimated.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 

The following automatic conversions were performed:

'_chemical_melting_point' value '205-206' was changed to '205.5(5)' -
the average value was taken and precision was estimated.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      'I 41/a'
_cod_database_code               2102176