The reaction of tertiary phosphines with (Ph2Se2I2)2‒the influence of steric and electronic effects.
Barnes, Nicholas A.; Godfrey, Stephen M.; Halton, Ruth T. A.; Mushtaq, Imrana; Pritchard, Robin G.; Dalton transactions (Cambridge, England : 2003)  (2006) 4795–4804; doi:10.1039/b608453b

data_7007668
_publ_section_title
;
 The reaction of tertiary phosphines with (Ph2Se2I2)2--the influence of
 steric and electronic effects.
;
_journal_issue                   40
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              4795
_journal_page_last               4804
_journal_paper_doi               10.1039/b608453b
_journal_year                    2006
_chemical_absolute_configuration unk
_chemical_compound_source        'synthesis as described'
_chemical_formula_moiety         'C19 H30 Cl2 I2 P2 Se2'
_chemical_formula_sum            'C19 H30 Cl2 I2 P2 Se2'
_chemical_formula_weight         802.99
_chemical_name_systematic
;
?
;
_space_group_IT_number           41
_symmetry_cell_setting           orthorhombic
_symmetry_Int_Tables_number      41
_symmetry_space_group_name_Hall  'A 2 -2ab'
_symmetry_space_group_name_H-M   'A b a 2'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_conform_dict_location     ftp://ftp.iucr.org/pub/cif_core.dic
_audit_conform_dict_name         cif_core.dic
_audit_conform_dict_version      2.3
_audit_creation_date             2005-07-03T12:24:18-00:00
_audit_creation_method           'WinGX routine CIF_UPDATE'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   12.0129(3)
_cell_length_b                   20.2339(4)
_cell_length_c                   11.7239(2)
_cell_measurement_reflns_used    8440
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      27
_cell_measurement_theta_min      3
_cell_measurement_wavelength     0.71073
_cell_volume                     2849.70(10)
_computing_cell_refinement       'HKL Scalepack (Otwinowski & Minor 1997)'
_computing_data_collection       'Collect (Nonius BV, 1997-2000)'
_computing_data_reduction
'HKL Denzo and Scalepack (Otwinowski & Minor 1997)'
_computing_molecular_graphics    'Ortep-3 for Windows (Farrugia, 1997)'
_computing_publication_material  'WinGX publication routines (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      150(2)
_diffrn_detector                 'CCD plate'
_diffrn_detector_area_resol_mean 9
_diffrn_measured_fraction_theta_full 0.957
_diffrn_measured_fraction_theta_max 0.957
_diffrn_measurement_device       '95mm CCD camera on \k-goniostat'
_diffrn_measurement_device_type  KappaCCD
_diffrn_measurement_method       'CCD rotation images, thick slices'
_diffrn_orient_matrix_type       'by Nonius Collect from scalepack cell'
_diffrn_orient_matrix_UB_11      0.546048E-1
_diffrn_orient_matrix_UB_12      -0.85857E-2
_diffrn_orient_matrix_UB_13      0.622934E-1
_diffrn_orient_matrix_UB_21      -0.654786E-1
_diffrn_orient_matrix_UB_22      -0.89862E-2
_diffrn_orient_matrix_UB_23      0.511547E-1
_diffrn_orient_matrix_UB_31      0.0025
_diffrn_orient_matrix_UB_32      -0.478338E-1
_diffrn_orient_matrix_UB_33      -0.207911E-1
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.030
_diffrn_reflns_av_unetI/netI     0.0304
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -27
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            12242
_diffrn_reflns_reduction_process
;
Scaled and merged with SORTAV
R.H. Blessing, (1987) Cryst. Rev. 1, 3-58
R.H. Blessing, (1989) J. Appl. Cryst. 22, 396-397
;
_diffrn_reflns_theta_full        29.11
_diffrn_reflns_theta_max         29.11
_diffrn_reflns_theta_min         2.63
_diffrn_source                   'Enraf Nonius FR590'
_exptl_absorpt_coefficient_mu    5.066
_exptl_absorpt_correction_T_max  0.7181
_exptl_absorpt_correction_T_min  0.4306
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
R.H. Blessing, Acta Cryst. (1995), A51, 33-38
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.872
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             1528
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.13
_exptl_crystal_size_min          0.07
_refine_diff_density_max         0.506
_refine_diff_density_min         -0.636
_refine_diff_density_rms         0.091
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.599(9)
_refine_ls_extinction_coef       0.00105(6)
_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   1.074
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     194
_refine_ls_number_reflns         3345
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.073
_refine_ls_R_factor_all          0.0259
_refine_ls_R_factor_gt           0.0233
_refine_ls_shift/su_max          0.006
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0174P)^2^+3.5825P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0473
_refine_ls_wR_factor_ref         0.0481
_reflns_number_gt                3185
_reflns_number_total             3343
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b608453b.txt
_cod_data_source_block           new
_cod_original_sg_symbol_Hall     'A 2 -2ac'
_cod_database_code               7007668