Relations between 77Se NMR chemical shifts of (phenylseleno)benzenes and their molecular structures derived from nine X-ray crystal structures
Oddershede, Jette; Henriksen, Lars; Larsen, Sine; Organic & Biomolecular Chemistry 1 (2003) 1053–; doi:10.1039/b211130f

data_7150470
_publ_section_title
;
 Relations between 77Se NMR chemical shifts of (phenylseleno)benzenes
 and their molecular structures derived from nine X-ray crystal
 structures
;
_journal_issue                   6
_journal_name_full               'Organic &amp;  Biomolecular Chemistry'
_journal_page_first              1053
_journal_paper_doi               10.1039/b211130f
_journal_volume                  1
_journal_year                    2003
_chemical_formula_moiety         'C22 H22 O2 Se2'
_chemical_formula_sum            'C22 H22 O2 Se2'
_chemical_formula_weight         476.32
_chemical_name_common            4
_chemical_name_systematic
; 
1,2-diethoxy-4,5-bis(phenylseleno)benzene 
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                116.25(2)
_cell_angle_beta                 100.280(17)
_cell_angle_gamma                104.48(2)
_cell_formula_units_Z            2
_cell_length_a                   8.5958(17)
_cell_length_b                   11.370(3)
_cell_length_c                   12.388(3)
_cell_measurement_reflns_used    20
_cell_measurement_temperature    122.0(5)
_cell_measurement_theta_max      41.50
_cell_measurement_theta_min      39.27
_cell_volume                     991.4(5)
_computing_cell_refinement       'CAD4 Express (1994)'
_computing_data_collection       'CAD4 Express (1994)'
_computing_data_reduction        'DREADD (Blessing 1987)'
_computing_molecular_graphics    'ORTEPII (Johnson, 1976)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      122.0(5)
_diffrn_measured_fraction_theta_full 0.963
_diffrn_measured_fraction_theta_max 0.963
_diffrn_measurement_device_type  'Enraf-Nonius CAD4'
_diffrn_measurement_method       \w--2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54180
_diffrn_reflns_av_R_equivalents  0.0290
_diffrn_reflns_av_sigmaI/netI    0.0299
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            6745
_diffrn_reflns_theta_full        74.91
_diffrn_reflns_theta_max         74.91
_diffrn_reflns_theta_min         4.22
_diffrn_standards_decay_%        4.6
_diffrn_standards_interval_time  167
_diffrn_standards_number         5
_exptl_absorpt_coefficient_mu    4.761
_exptl_absorpt_correction_T_max  0.177
_exptl_absorpt_correction_T_min  0.046
_exptl_absorpt_correction_type   integration
_exptl_absorpt_process_details   '(DeTitta, 1985)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.596
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             476
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.08
_exptl_crystal_size_min          0.07
_refine_diff_density_max         1.960
_refine_diff_density_min         -0.912
_refine_diff_density_rms         0.089
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.094
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     227
_refine_ls_number_reflns         3936
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.094
_refine_ls_R_factor_all          0.0355
_refine_ls_R_factor_gt           0.0349
_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^)+(0.0256P)^2^+2.6667P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0863
_refine_ls_wR_factor_ref         0.0867
_reflns_number_gt                3868
_reflns_number_total             3936
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b211130f.txt
_cod_data_source_block           4
_cod_database_code               7150470