(18-Crown-6)-μ-oxo-hexakis(tetrahydroborato)diuranium(IV): an unprecedented asymmetric dinuclear complex
Villiers, Claude; Thuéry, Pierre; Ephritikhine, Michel; Acta Crystallographica Section C 62 (2006) m243–m245; doi:10.1107/S0108270106014934

data_2015370
_publ_section_title
;
 (18-Crown-6)-\m-oxo-hexakis(tetrahydroborato)diuranium(IV): an
 unprecedented asymmetric dinuclear complex
;
_journal_coeditor_code           GG3015
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              m243
_journal_page_last               m245
_journal_paper_doi               10.1107/S0108270106014934
_journal_volume                  62
_journal_year                    2006
_chemical_formula_iupac          '[U2 (B H4)6 O (C12 H24 O6)]'
_chemical_formula_moiety         'C12 H48 B6 O7 U2'
_chemical_formula_sum            'C12 H48 B6 O7 U2'
_chemical_formula_weight         845.42
_chemical_name_common
;
(18-Crown-6)-\m-oxo-hexakis(tetrahydroborato)diuranium(IV)
;
_chemical_name_systematic
;
(1,4,7,10,13,16-hexaoxacyclooctadecane-1\k^6^O)-\m-oxo-1:2\k^2^O:O-
hexakis(tetrahydroborato)-1\k^3^H;2\k^4^H;2\k^9^H-diuranium(IV)
;
_space_group_IT_number           29
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2ac'
_symmetry_space_group_name_H-M   'P c a 21'
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_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   16.4251(7)
_cell_length_b                   10.2676(5)
_cell_length_c                   16.3550(7)
_cell_measurement_reflns_used    17685
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      25.68
_cell_measurement_theta_min      3.18
_cell_volume                     2758.2(2)
_computing_cell_refinement       'HKL2000 (Otwinowski & Minor, 1997)'
_computing_data_collection       'COLLECT (Nonius, 1998)'
_computing_data_reduction        HKL2000
_computing_molecular_graphics    'SHELXTL (Bruker, 1999)'
_computing_publication_material  'SHELXTL and PLATON (Spek, 2003)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 18
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Nonius KappaCCD area-detector'
_diffrn_measurement_method       \f
_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  0.0617
_diffrn_reflns_av_sigmaI/netI    0.0564
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -20
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            17685
_diffrn_reflns_theta_full        25.68
_diffrn_reflns_theta_max         25.68
_diffrn_reflns_theta_min         3.18
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    11.752
_exptl_absorpt_correction_T_max  0.309
_exptl_absorpt_correction_T_min  0.287
_exptl_absorpt_correction_type   refdelf
_exptl_absorpt_process_details   '(DELABS in PLATON; Spek, 2003)'
_exptl_crystal_colour            'translucent light green'
_exptl_crystal_density_diffrn    2.036
_exptl_crystal_description       irregular
_exptl_crystal_F_000             1560
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.12
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.737
_refine_diff_density_min         -0.960
_refine_ls_abs_structure_details 'Flack (1983), with how many Friedel pairs?'
_refine_ls_abs_structure_Flack   0.006(12)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.026
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     245
_refine_ls_number_reflns         5193
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.026
_refine_ls_R_factor_all          0.0368
_refine_ls_R_factor_gt           0.0293
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0073P)^2^+3.4303P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0570
_refine_ls_wR_factor_ref         0.0590
_reflns_number_gt                4656
_reflns_number_total             5193
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            gg3015.cif
_cod_data_source_block           I
_cod_database_code               2015370
_cod_database_fobs_code          2015370