Exploring hypervalency and three-centre, four-electron bonding interactions: Reactions of acenaphthene chalcogen donors and dihalogen acceptors.
Knight, Fergus R.; Athukorala Arachchige, Kasun S.; Randall, Rebecca A. M.; Bühl, Michael; Slawin, Alexandra M. Z.; Woollins, J. Derek; Dalton transactions (Cambridge, England : 2003) 41 (2012) 3154–3165; doi:10.1039/c2dt12031c

data_7018228
_publ_section_title
;
 Exploring hypervalency and three-centre, four-electron bonding
 interactions: Reactions of acenaphthene chalcogen donors and dihalogen
 acceptors.
;
_journal_issue                   11
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              3154
_journal_page_last               3165
_journal_paper_doi               10.1039/c2dt12031c
_journal_volume                  41
_journal_year                    2012
_chemical_formula_moiety         'C24 H18 Se2 I2'
_chemical_formula_sum            'C24 H18 I2 Se2'
_chemical_formula_weight         718.14
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      14
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.0000
_cell_angle_beta                 97.390(13)
_cell_angle_gamma                90.0000
_cell_formula_units_Z            4
_cell_length_a                   9.555(5)
_cell_length_b                   8.242(4)
_cell_length_c                   28.147(14)
_cell_measurement_reflns_used    7869
_cell_measurement_temperature    125
_cell_measurement_theta_max      29.13
_cell_measurement_theta_min      1.46
_cell_volume                     2198.2(19)
_computing_cell_refinement       'CrystalClear-SM Expert 2.0 r2'
_computing_data_collection       'CrystalClear-SM Expert 2.0 r2 (Rigaku, 2009)'
_computing_data_reduction        'CrystalClear-SM Expert 2.0 r2'
_computing_molecular_graphics    'CrystalStructure 4.0'
_computing_publication_material  'CrystalStructure 4.0 (Rigaku, 2010)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      125
_diffrn_detector_area_resol_mean 28.944
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.869
_diffrn_measurement_device_type  'Rigaku Saturn724 CCD'
_diffrn_measurement_method       \w
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71075
_diffrn_reflns_av_R_equivalents  0.1087
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       38
_diffrn_reflns_limit_l_min       -36
_diffrn_reflns_number            19164
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         29.10
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    6.182
_exptl_absorpt_correction_T_max  0.290
_exptl_absorpt_correction_T_min  0.152
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Jacobson, R. (1998) Private communication'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    2.170
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             1344.00
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.20
_refine_diff_density_max         2.290
_refine_diff_density_min         -2.480
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.274
_refine_ls_hydrogen_treatment    constr
_refine_ls_number_parameters     253
_refine_ls_number_reflns         5113
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.1343
_refine_ls_R_factor_gt           0.0952
_refine_ls_shift/su_max          0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.1327P)^2^+20.2076P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         0.3043
_reflns_number_gt                3940
_reflns_number_total             5470
_reflns_threshold_expression     F^2^>2.0\s(F^2^)
_cod_data_source_file            c2dt12031c.txt
_cod_data_source_block           '_Ferg88-2off'
_cod_original_cell_volume        2198.4(20)
_cod_original_formula_sum        'C24 H18 Se2 I2'
_cod_database_code               7018228