##############################################################################
###                                                                        ###
###           Full Paper (Acta Crystallographica Section C)                ###
###                                                                        ###
##############################################################################
#                                                                            #
# This CIF contains the data in a paper accepted for publication in Acta     #
# Crystallographica Section C. It conforms to the editorial and technical    #
# requirements of Notes for Authors for Section C, and has been peer         #
# reviewed under the auspices of the IUCr Commission on Journals.            #
#                                                                            #
# Full details of the Crystallographic Information File format               #
# are given in the paper "The Crystallographic Information File (CIF):       #
# a New Standard Archive File for Crystallography" by S. R. Hall, F. H.      #
# Allen and I. D. Brown [Acta Cryst. (1991), A47, 655-685].                  #
#                                                                            #
# The current version of the core CIF dictionary is obtainable from          #
# ftp://ftp.iucr.org/pub/cif_core.dic. The current version number is 2.4.    #
#                                                                            #
# Software is freely available for graphical display of the structure(s) in  #
# this CIF.  For information consult the CIF home page http://www.iucr.org/  #
# cif/home.html                                                              #
#                                                                            #
# This file may be used for bona fide research purposes within the           #
# scientific community so long as proper attribution is given to the journal # 
# article from which it was obtained.                                        #
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data_I
_audit_creation_method     'SHELXL97 + hand edit'
_chemical_name_systematic
;
μ-oxido-bis[(tert-butylselenolato)bis(η⁵-cyclopentadienyl)niobium(IV)]
toluene solvate
;
_chemical_name_common     ?
_chemical_formula_moiety     'C28 H38 Nb2 O Se2 , C7 H8'
_chemical_formula_sum     'C35 H46 Nb2 O Se2'
_chemical_formula_structural     '[Nb2 (C5 H5)4 (C4 H9 Se)2 O] , C7 H8'
_chemical_formula_iupac     '[Nb2 (C5 H5)4 (C4 H9 Se)2 O] , C7 H8'
_chemical_formula_weight     826.46
_chemical_melting_point     ?
_symmetry_cell_setting     monoclinic
_symmetry_space_group_name_H-M     'P 21/n'
_symmetry_space_group_name_Hall     '-P 2yn'
loop_
    _symmetry_equiv_pos_as_xyz
    'x, y, z'
    '-x+1/2, y+1/2, -z+1/2'
    '-x, -y, -z'
    'x-1/2, -y-1/2, z-1/2'
_cell_length_a     8.0288(10)
_cell_length_b     12.7685(15)
_cell_length_c     15.873(2)
_cell_angle_alpha     90.00
_cell_angle_beta     92.848(6)
_cell_angle_gamma     90.00
_cell_volume     1625.3(3)
_cell_formula_units_Z     2
_cell_measurement_reflns_used     24097
_cell_measurement_theta_min     2.91
_cell_measurement_theta_max     27.48
_cell_measurement_temperature     120(2)
_exptl_crystal_description     needle
_exptl_crystal_colour     blue
_exptl_crystal_size_max     0.14
_exptl_crystal_size_mid     0.06
_exptl_crystal_size_min     0.02
_exptl_crystal_density_diffrn     1.689
_exptl_crystal_density_meas     ?
_exptl_crystal_density_method     'not measured'
_exptl_crystal_F_000     828
_exptl_absorpt_coefficient_mu     2.971
_exptl_absorpt_correction_type     multi-scan
_exptl_absorpt_process_details     '(SADABS; Sheldrick, 2007)'
_exptl_absorpt_correction_T_min     0.7311
_exptl_absorpt_correction_T_max     0.9400
_exptl_special_details
;
;
_diffrn_ambient_temperature     120(2)
_diffrn_radiation_type     MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_radiation_source     'Bruker Nonius FR591 rotating anode'
_diffrn_radiation_monochromator     '10cm confocal mirrors'
_diffrn_measurement_device_type
                                 'Bruker Nonius 95mm CCD camera on κ-goniostat'
_diffrn_measurement_method     'φ and ω scans'
_diffrn_detector_area_resol_mean     ?
_diffrn_reflns_number     21963
_diffrn_reflns_av_R_equivalents     0.0302
_diffrn_reflns_av_sigmaI/netI     0.0260
_diffrn_reflns_theta_min     3.21
_diffrn_reflns_theta_max     27.51
_diffrn_reflns_theta_full     27.51
_diffrn_measured_fraction_theta_max     0.993
_diffrn_measured_fraction_theta_full     0.993
_diffrn_reflns_limit_h_min     -8
_diffrn_reflns_limit_h_max     10
_diffrn_reflns_limit_k_min     -16
_diffrn_reflns_limit_k_max     16
_diffrn_reflns_limit_l_min     -20
_diffrn_reflns_limit_l_max     18
_diffrn_standards_number     0
_diffrn_standards_interval_count     ?
_diffrn_standards_interval_time     ?
_diffrn_standards_decay_%     ?
_refine_special_details
;
Refinement of F² against ALL reflections. The weighted R-factor
wR and goodness of fit S are based on F², conventional
R-factors R are based on F, with F set to zero for
negative F². The threshold expression of F² >
σ(F²) is used only for calculating R-factors(gt) etc.
and is not relevant to the choice of reflections for refinement.
R-factors based on F² are statistically about twice as large
as those based on F, and R- factors based on ALL data will be
even larger.
;
_reflns_number_total     3729
_reflns_number_gt     3323
_reflns_threshold_expression     I>2σ(I)
_refine_ls_structure_factor_coef     Fsqd
_refine_ls_matrix_type     full
_refine_ls_R_factor_all     0.0305
_refine_ls_R_factor_gt     0.0237
_refine_ls_wR_factor_gt     0.0478
_refine_ls_wR_factor_ref     0.0511
_refine_ls_goodness_of_fit_ref     1.171
_refine_ls_restrained_S_all     1.171
_refine_ls_number_reflns     3729
_refine_ls_number_parameters     206
_refine_ls_number_restraints     0
_refine_ls_hydrogen_treatment     constr
_refine_ls_weighting_scheme     calc
_refine_ls_weighting_details
            'w = 1/[σ²(Fo²)+(0.0086P)²+1.6817P] where P=(Fo²+2Fc²)/3'
_atom_sites_solution_hydrogens     geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary     difmap
_refine_ls_shift/su_max     0.001
_refine_ls_shift/su_mean     0.000
_refine_diff_density_max     0.435
_refine_diff_density_min     -0.573
_refine_ls_extinction_method     none
_refine_ls_extinction_coef     ?
loop_
    _atom_type_symbol
    _atom_type_description
    _atom_type_scat_dispersion_real
    _atom_type_scat_dispersion_imag
    _atom_type_scat_source
    'C' 'C' 0.0033 0.0016
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
    'H' 'H' 0.0000 0.0000
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
    'Se' 'Se' -0.0929 2.2259
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
    'Nb' 'Nb' -2.0727 0.6215
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
    'O' 'O' 0.0106 0.0060
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
_computing_data_collection
;
COLLECT (Nonius, 1998) and DENZO (Otwinowski & Minor, 1997)
;
_computing_cell_refinement
;
COLLECT (Nonius, 1998) and DENZO (Otwinowski & Minor, 1997)
;
_computing_data_reduction
;
COLLECT (Nonius, 1998) and DENZO (Otwinowski & Minor, 1997)
;
_computing_structure_solution     'SHELXS97 (Sheldrick, 2008)'
_computing_structure_refinement     'SHELXL97 (Sheldrick, 2008)'
_computing_molecular_graphics     'ORTEPII (Johnson, 1976)'
_computing_publication_material     'SHELXL97 (Sheldrick, 2008)'
loop_
    _atom_site_type_symbol
    _atom_site_label
    _atom_site_fract_x
    _atom_site_fract_y
    _atom_site_fract_z
    _atom_site_U_iso_or_equiv
    _atom_site_adp_type
    _atom_site_calc_flag
    _atom_site_refinement_flags
    _atom_site_occupancy
    _atom_site_disorder_assembly
    _atom_site_disorder_group
    Nb Nb1 0.86675(2) 0.045165(15) 0.902140(12) 0.01596(6) Uani d . 1 . .
    Se Se1 1.16711(3) 0.088095(17) 0.852676(13) 0.01894(6) Uani d . 1 . .
    O O1 1.0000 0.0000 1.0000 0.0175(4) Uani d S 1 . .
    C C1 0.8267(3) 0.23334(18) 0.88319(15) 0.0280(5) Uani d . 1 . .
    H H1 0.8904 0.2699 0.8438 0.034 Uiso calc R 1 . .
    C C2 0.6699(3) 0.1887(2) 0.86687(16) 0.0332(6) Uani d . 1 . .
    H H2 0.6077 0.1900 0.8144 0.040 Uiso calc R 1 . .
    C C3 0.6197(3) 0.14135(19) 0.94186(17) 0.0311(6) Uani d . 1 . .
    H H3 0.5183 0.1045 0.9483 0.037 Uiso calc R 1 . .
    C C4 0.7445(3) 0.15800(18) 1.00495(15) 0.0245(5) Uani d . 1 . .
    H H4 0.7426 0.1354 1.0619 0.029 Uiso calc R 1 . .
    C C5 0.8736(3) 0.21437(17) 0.96879(14) 0.0217(5) Uani d . 1 . .
    H H5 0.9748 0.2360 0.9971 0.026 Uiso calc R 1 . .
    C C6 0.7174(3) -0.03132(19) 0.77639(15) 0.0265(5) Uani d . 1 . .
    H H6 0.6745 0.0126 0.7321 0.032 Uiso calc R 1 . .
    C C7 0.6332(3) -0.06054(19) 0.84833(16) 0.0280(5) Uani d . 1 . .
    H H7 0.5233 -0.0402 0.8610 0.034 Uiso calc R 1 . .
    C C8 0.7408(3) -0.12557(18) 0.89862(15) 0.0267(5) Uani d . 1 . .
    H H8 0.7168 -0.1563 0.9512 0.032 Uiso calc R 1 . .
    C C9 0.8900(3) -0.13632(17) 0.85629(14) 0.0235(5) Uani d . 1 . .
    H H9 0.9844 -0.1762 0.8754 0.028 Uiso calc R 1 . .
    C C10 0.8760(3) -0.07818(18) 0.78117(14) 0.0229(5) Uani d . 1 . .
    H H10 0.9589 -0.0717 0.7408 0.028 Uiso calc R 1 . .
    C C11 1.1745(3) 0.16368(18) 0.74104(14) 0.0219(5) Uani d . 1 . .
    C C12 1.3076(3) 0.1089(2) 0.69162(15) 0.0300(5) Uani d . 1 . .
    H H12A 1.2755 0.0357 0.6819 0.045 Uiso calc R 1 . .
    H H12B 1.4147 0.1117 0.7239 0.045 Uiso calc R 1 . .
    H H12C 1.3179 0.1442 0.6373 0.045 Uiso calc R 1 . .
    C C13 1.0094(3) 0.16079(19) 0.68959(14) 0.0256(5) Uani d . 1 . .
    H H13A 0.9226 0.1939 0.7217 0.038 Uiso calc R 1 . .
    H H13B 0.9786 0.0879 0.6774 0.038 Uiso calc R 1 . .
    H H13C 1.0208 0.1987 0.6365 0.038 Uiso calc R 1 . .
    C C14 1.2255(3) 0.27681(19) 0.75989(15) 0.0284(5) Uani d . 1 . .
    H H14A 1.2388 0.3143 0.7068 0.043 Uiso calc R 1 . .
    H H14B 1.3314 0.2776 0.7934 0.043 Uiso calc R 1 . .
    H H14C 1.1391 0.3111 0.7916 0.043 Uiso calc R 1 . .
    C C15 0.930(3) -0.073(3) 0.540(2) 0.038(3) Uani d P 0.50 A -1
    H H15 0.9500 -0.1398 0.5652 0.046 Uiso calc PR 0.50 A -1
    C C16 0.7745(8) -0.0246(4) 0.5405(4) 0.0386(13) Uani d P 0.50 A -1
    H H16 0.6845 -0.0594 0.5652 0.046 Uiso calc PR 0.50 A -1
    C C17 0.750(5) 0.069(3) 0.507(2) 0.0479(19) Uani d P 0.50 A -1
    H H17 0.6428 0.1000 0.5090 0.058 Uiso calc PR 0.50 A -1
    C C18 0.8708(9) 0.1250(4) 0.4686(3) 0.0435(15) Uani d P 0.50 A -1
    H H18 0.8506 0.1920 0.4442 0.052 Uiso calc PR 0.50 A -1
    C C15A 1.028(3) 0.075(3) 0.4684(19) 0.038(3) Uani d P 0.50 A -1
    H H15A 1.1166 0.1110 0.4432 0.046 Uiso calc PR 0.50 A -1
    C C19 1.0579(7) -0.0164(4) 0.5009(3) 0.0360(13) Uani d P 0.50 A -1
    C C17A 1.239(5) -0.069(3) 0.499(3) 0.0479(19) Uani d P 0.50 A -1
    H H17A 1.2603 -0.1101 0.5510 0.072 Uiso calc PR 0.50 A -1
    H H17B 1.3236 -0.0145 0.4958 0.072 Uiso calc PR 0.50 A -1
    H H17C 1.2430 -0.1155 0.4502 0.072 Uiso calc PR 0.50 A -1
_geom_special_details
;
All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes)
are estimated using the full covariance matrix. The cell e.s.d.'s are taken
into account individually in the estimation of e.s.d.'s in distances, angles
and torsion angles; correlations between e.s.d.'s in cell parameters are only
used when they are defined by crystal symmetry. An approximate (isotropic)
treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s.
planes.
;
loop_
    _geom_bond_atom_site_label_1
    _geom_bond_atom_site_label_2
    _geom_bond_site_symmetry_2
    _geom_bond_distance
    _geom_bond_publ_flag
    Nb1 O1 . 1.9300(3) y
    Nb1 Se1 . 2.6307(4) y
    Se1 C11 . 2.021(2) y
    C11 C12 . 1.526(3) n
    C11 C13 . 1.523(3) n
    C11 C14 . 1.527(3) n
    Nb1 C8 . 2.403(2) ?
    Nb1 C5 . 2.405(2) ?
    Nb1 C4 . 2.421(2) ?
    Nb1 C7 . 2.431(2) ?
    Nb1 C9 . 2.439(2) ?
    Nb1 C1 . 2.441(2) ?
    Nb1 C3 . 2.442(2) ?
    Nb1 C2 . 2.466(2) ?
    Nb1 C6 . 2.477(2) ?
    Nb1 C10 . 2.487(2) ?
    O1 Nb1 3_757 1.9300(3) ?
    C1 C2 . 1.394(4) ?
    C1 C5 . 1.413(3) ?
    C1 H1 . 0.9500 ?
    C2 C3 . 1.412(4) ?
    C2 H2 . 0.9500 ?
    C3 C4 . 1.398(3) ?
    C3 H3 . 0.9500 ?
    C4 C5 . 1.407(3) ?
    C4 H4 . 0.9500 ?
    C5 H5 . 0.9500 ?
    C6 C10 . 1.405(3) ?
    C6 C7 . 1.406(4) ?
    C6 H6 . 0.9500 ?
    C7 C8 . 1.416(3) ?
    C7 H7 . 0.9500 ?
    C8 C9 . 1.409(3) ?
    C8 H8 . 0.9500 ?
    C9 C10 . 1.404(3) ?
    C9 H9 . 0.9500 ?
    C10 H10 . 0.9500 ?
    C12 H12A . 0.9800 ?
    C12 H12B . 0.9800 ?
    C12 H12C . 0.9800 ?
    C13 H13A . 0.9800 ?
    C13 H13B . 0.9800 ?
    C13 H13C . 0.9800 ?
    C14 H14A . 0.9800 ?
    C14 H14B . 0.9800 ?
    C14 H14C . 0.9800 ?
    C15 C16 . 1.40(3) ?
    C15 C19 . 1.42(3) ?
    C15 H15 . 0.9500 ?
    C16 C17 . 1.33(4) ?
    C16 H16 . 0.9500 ?
    C17 C18 . 1.36(4) ?
    C17 H17 . 0.9500 ?
    C18 C15A . 1.41(3) ?
    C18 H18 . 0.9500 ?
    C15A C19 . 1.30(4) ?
    C15A H15A . 0.9500 ?
    C19 C17A . 1.60(4) ?
    C17A H17A . 0.9800 ?
    C17A H17B . 0.9800 ?
    C17A H17C . 0.9800 ?
loop_
    _geom_angle_atom_site_label_1
    _geom_angle_atom_site_label_2
    _geom_angle_atom_site_label_3
    _geom_angle_site_symmetry_1
    _geom_angle_site_symmetry_3
    _geom_angle
    _geom_angle_publ_flag
    Nb1 O1 Nb1 . 3_757 180 y
    O1 Nb1 Se1 . . 79.791(11) y
    C11 Se1 Nb1 . . 115.38(6) y
    O1 Nb1 C8 . . 87.90(6) ?
    O1 Nb1 C5 . . 85.11(5) ?
    C8 Nb1 C5 . . 145.65(8) ?
    O1 Nb1 C4 . . 82.08(6) ?
    C8 Nb1 C4 . . 111.80(8) ?
    C5 Nb1 C4 . . 33.90(8) ?
    O1 Nb1 C7 . . 120.27(6) ?
    C8 Nb1 C7 . . 34.06(8) ?
    C5 Nb1 C7 . . 130.82(8) ?
    C4 Nb1 C7 . . 103.64(8) ?
    O1 Nb1 C9 . . 84.76(5) ?
    C8 Nb1 C9 . . 33.84(8) ?
    C5 Nb1 C9 . . 169.87(8) ?
    C4 Nb1 C9 . . 143.73(8) ?
    C7 Nb1 C9 . . 55.72(8) ?
    O1 Nb1 C1 . . 117.24(6) ?
    C8 Nb1 C1 . . 146.88(9) ?
    C5 Nb1 C1 . . 33.89(8) ?
    C4 Nb1 C1 . . 56.07(8) ?
    C7 Nb1 C1 . . 114.11(9) ?
    C9 Nb1 C1 . . 155.52(8) ?
    O1 Nb1 C3 . . 111.55(7) ?
    C8 Nb1 C3 . . 96.66(9) ?
    C5 Nb1 C3 . . 55.65(8) ?
    C4 Nb1 C3 . . 33.40(8) ?
    C7 Nb1 C3 . . 75.38(8) ?
    C9 Nb1 C3 . . 129.06(8) ?
    C1 Nb1 C3 . . 55.46(9) ?
    O1 Nb1 C2 . . 136.73(6) ?
    C8 Nb1 C2 . . 113.89(9) ?
    C5 Nb1 C2 . . 55.43(8) ?
    C4 Nb1 C2 . . 55.54(8) ?
    C7 Nb1 C2 . . 81.87(9) ?
    C9 Nb1 C2 . . 134.12(8) ?
    C1 Nb1 C2 . . 32.99(9) ?
    C3 Nb1 C2 . . 33.43(9) ?
    O1 Nb1 C6 . . 139.23(6) ?
    C8 Nb1 C6 . . 55.76(8) ?
    C5 Nb1 C6 . . 135.08(8) ?
    C4 Nb1 C6 . . 125.57(8) ?
    C7 Nb1 C6 . . 33.28(9) ?
    C9 Nb1 C6 . . 54.98(8) ?
    C1 Nb1 C6 . . 103.48(8) ?
    C3 Nb1 C6 . . 92.27(8) ?
    C2 Nb1 C6 . . 80.28(8) ?
    O1 Nb1 C10 . . 113.30(5) ?
    C8 Nb1 C10 . . 55.68(8) ?
    C5 Nb1 C10 . . 155.16(8) ?
    C4 Nb1 C10 . . 157.79(8) ?
    C7 Nb1 C10 . . 55.20(8) ?
    C9 Nb1 C10 . . 33.11(8) ?
    C1 Nb1 C10 . . 122.47(8) ?
    C3 Nb1 C10 . . 124.99(8) ?
    C2 Nb1 C10 . . 109.80(8) ?
    C6 Nb1 C10 . . 32.88(8) ?
    C8 Nb1 Se1 . . 124.97(6) ?
    C5 Nb1 Se1 . . 86.73(6) ?
    C4 Nb1 Se1 . . 119.04(6) ?
    C7 Nb1 Se1 . . 135.52(6) ?
    C9 Nb1 Se1 . . 91.37(6) ?
    C1 Nb1 Se1 . . 82.84(6) ?
    C3 Nb1 Se1 . . 137.78(6) ?
    C2 Nb1 Se1 . . 111.34(7) ?
    C6 Nb1 Se1 . . 104.82(6) ?
    C10 Nb1 Se1 . . 80.71(6) ?
    C2 C1 C5 . . 107.7(2) ?
    C2 C1 Nb1 . . 74.50(14) ?
    C5 C1 Nb1 . . 71.67(13) ?
    C2 C1 H1 . . 126.2 ?
    C5 C1 H1 . . 126.2 ?
    Nb1 C1 H1 . . 119.5 ?
    C1 C2 C3 . . 108.2(2) ?
    C1 C2 Nb1 . . 72.50(13) ?
    C3 C2 Nb1 . . 72.36(13) ?
    C1 C2 H2 . . 125.9 ?
    C3 C2 H2 . . 125.9 ?
    Nb1 C2 H2 . . 121.0 ?
    C4 C3 C2 . . 108.3(2) ?
    C4 C3 Nb1 . . 72.46(13) ?
    C2 C3 Nb1 . . 74.21(14) ?
    C4 C3 H3 . . 125.8 ?
    C2 C3 H3 . . 125.8 ?
    Nb1 C3 H3 . . 119.3 ?
    C3 C4 C5 . . 107.6(2) ?
    C3 C4 Nb1 . . 74.15(14) ?
    C5 C4 Nb1 . . 72.43(13) ?
    C3 C4 H4 . . 126.2 ?
    C5 C4 H4 . . 126.2 ?
    Nb1 C4 H4 . . 119.1 ?
    C4 C5 C1 . . 108.3(2) ?
    C4 C5 Nb1 . . 73.67(13) ?
    C1 C5 Nb1 . . 74.44(13) ?
    C4 C5 H5 . . 125.9 ?
    C1 C5 H5 . . 125.9 ?
    Nb1 C5 H5 . . 118.0 ?
    C10 C6 C7 . . 108.3(2) ?
    C10 C6 Nb1 . . 73.95(13) ?
    C7 C6 Nb1 . . 71.54(13) ?
    C10 C6 H6 . . 125.8 ?
    C7 C6 H6 . . 125.8 ?
    Nb1 C6 H6 . . 120.4 ?
    C6 C7 C8 . . 108.0(2) ?
    C6 C7 Nb1 . . 75.18(13) ?
    C8 C7 Nb1 . . 71.87(13) ?
    C6 C7 H7 . . 126.0 ?
    C8 C7 H7 . . 126.0 ?
    Nb1 C7 H7 . . 118.8 ?
    C9 C8 C7 . . 107.3(2) ?
    C9 C8 Nb1 . . 74.49(13) ?
    C7 C8 Nb1 . . 74.06(13) ?
    C9 C8 H8 . . 126.3 ?
    C7 C8 H8 . . 126.3 ?
    Nb1 C8 H8 . . 117.2 ?
    C10 C9 C8 . . 108.6(2) ?
    C10 C9 Nb1 . . 75.35(13) ?
    C8 C9 Nb1 . . 71.67(13) ?
    C10 C9 H9 . . 125.7 ?
    C8 C9 H9 . . 125.7 ?
    Nb1 C9 H9 . . 119.1 ?
    C9 C10 C6 . . 107.8(2) ?
    C9 C10 Nb1 . . 71.55(13) ?
    C6 C10 Nb1 . . 73.17(13) ?
    C9 C10 H10 . . 126.1 ?
    C6 C10 H10 . . 126.1 ?
    Nb1 C10 H10 . . 120.9 ?
    C13 C11 C12 . . 109.04(19) ?
    C13 C11 C14 . . 110.22(19) ?
    C12 C11 C14 . . 110.3(2) ?
    C13 C11 Se1 . . 113.31(15) ?
    C12 C11 Se1 . . 106.49(15) ?
    C14 C11 Se1 . . 107.41(15) ?
    C11 C12 H12A . . 109.5 ?
    C11 C12 H12B . . 109.5 ?
    H12A C12 H12B . . 109.5 ?
    C11 C12 H12C . . 109.5 ?
    H12A C12 H12C . . 109.5 ?
    H12B C12 H12C . . 109.5 ?
    C11 C13 H13A . . 109.5 ?
    C11 C13 H13B . . 109.5 ?
    H13A C13 H13B . . 109.5 ?
    C11 C13 H13C . . 109.5 ?
    H13A C13 H13C . . 109.5 ?
    H13B C13 H13C . . 109.5 ?
    C11 C14 H14A . . 109.5 ?
    C11 C14 H14B . . 109.5 ?
    H14A C14 H14B . . 109.5 ?
    C11 C14 H14C . . 109.5 ?
    H14A C14 H14C . . 109.5 ?
    H14B C14 H14C . . 109.5 ?
    C16 C15 C19 . . 116(3) ?
    C16 C15 H15 . . 121.9 ?
    C19 C15 H15 . . 121.9 ?
    C17 C16 C15 . . 121(2) ?
    C17 C16 H16 . . 119.6 ?
    C15 C16 H16 . . 119.6 ?
    C16 C17 C18 . . 124(3) ?
    C16 C17 H17 . . 118.0 ?
    C18 C17 H17 . . 118.0 ?
    C17 C18 C15A . . 115(2) ?
    C17 C18 H18 . . 122.5 ?
    C15A C18 H18 . . 122.5 ?
    C19 C15A C18 . . 123.5(19) ?
    C19 C15A H15A . . 118.2 ?
    C18 C15A H15A . . 118.2 ?
    C15A C19 C15 . . 120.7(19) ?
    C15A C19 C17A . . 121.6(18) ?
    C15 C19 C17A . . 118(2) ?
data_II
_audit_creation_method     'SHELXL97 + hand edit'
_chemical_name_systematic
;
μ-selenido-bis[(tert-butylselenolato)bis(η⁵-cyclopentadienyl)niobium(IV)]
;
_chemical_name_common     ?
_chemical_formula_moiety     'C28 H38 Nb2 Se3'
_chemical_formula_sum     'C28 H38 Nb2 Se3'
_chemical_formula_structural     '[Nb2 (C5 H5)4 (C4 H9 Se)2 Se]'
_chemical_formula_iupac     '[Nb2 (C5 H5)4 (C4 H9 Se)2 Se]'
_chemical_formula_weight     797.28
_chemical_melting_point     ?
_symmetry_cell_setting     monoclinic
_symmetry_space_group_name_H-M     'C 2/c'
_symmetry_space_group_name_Hall     '-C 2yc'
loop_
    _symmetry_equiv_pos_as_xyz
    'x, y, z'
    '-x, y, -z+1/2'
    'x+1/2, y+1/2, z'
    '-x+1/2, y+1/2, -z+1/2'
    '-x, -y, -z'
    'x, -y, z-1/2'
    '-x+1/2, -y+1/2, -z'
    'x+1/2, -y+1/2, z-1/2'
_cell_length_a     31.583(8)
_cell_length_b     7.9548(15)
_cell_length_c     26.520(7)
_cell_angle_alpha     90.00
_cell_angle_beta     121.29(2)
_cell_angle_gamma     90.00
_cell_volume     5694(3)
_cell_formula_units_Z     8
_cell_measurement_reflns_used     10429
_cell_measurement_theta_min     2.91
_cell_measurement_theta_max     27.48
_cell_measurement_temperature     120(2)
_exptl_crystal_description     block
_exptl_crystal_colour     blue
_exptl_crystal_size_max     0.12
_exptl_crystal_size_mid     0.09
_exptl_crystal_size_min     0.06
_exptl_crystal_density_diffrn     1.860
_exptl_crystal_density_meas     ?
_exptl_crystal_density_method     'not measured'
_exptl_crystal_F_000     3120
_exptl_absorpt_coefficient_mu     4.656
_exptl_absorpt_correction_type     multi-scan
_exptl_absorpt_process_details     '(SADABS; Sheldrick, 2007)'
_exptl_absorpt_correction_T_min     0.5136
_exptl_absorpt_correction_T_max     0.7560
_exptl_special_details
;
;
_diffrn_ambient_temperature     120(2)
_diffrn_radiation_type     MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_radiation_source     'Bruker Nonius FR591 rotating anode'
_diffrn_radiation_monochromator     'graphite'
_diffrn_measurement_device_type
                                 'Bruker Nonius 95mm CCD camera on κ-goniostat'
_diffrn_measurement_method     'φ and ω scans'
_diffrn_detector_area_resol_mean     ?
_diffrn_reflns_number     31432
_diffrn_reflns_av_R_equivalents     0.0832
_diffrn_reflns_av_sigmaI/netI     0.0763
_diffrn_reflns_theta_min     2.99
_diffrn_reflns_theta_max     27.57
_diffrn_reflns_theta_full     27.57
_diffrn_measured_fraction_theta_max     0.993
_diffrn_measured_fraction_theta_full     0.993
_diffrn_reflns_limit_h_min     -40
_diffrn_reflns_limit_h_max     40
_diffrn_reflns_limit_k_min     -10
_diffrn_reflns_limit_k_max     10
_diffrn_reflns_limit_l_min     -34
_diffrn_reflns_limit_l_max     34
_diffrn_standards_number     0
_diffrn_standards_interval_count     ?
_diffrn_standards_interval_time     ?
_diffrn_standards_decay_%     ?
_refine_special_details
;
Refinement of F² against ALL reflections. The weighted R-factor
wR and goodness of fit S are based on F², conventional
R-factors R are based on F, with F set to zero for
negative F². The threshold expression of F² >
σ(F²) is used only for calculating R-factors(gt) etc.
and is not relevant to the choice of reflections for refinement.
R-factors based on F² are statistically about twice as large
as those based on F, and R- factors based on ALL data will be
even larger.
;
_reflns_number_total     6538
_reflns_number_gt     4694
_reflns_threshold_expression     I>2σ(I)
_refine_ls_structure_factor_coef     Fsqd
_refine_ls_matrix_type     full
_refine_ls_R_factor_all     0.0744
_refine_ls_R_factor_gt     0.0413
_refine_ls_wR_factor_gt     0.0668
_refine_ls_wR_factor_ref     0.0746
_refine_ls_goodness_of_fit_ref     1.022
_refine_ls_restrained_S_all     1.041
_refine_ls_number_reflns     6538
_refine_ls_number_parameters     298
_refine_ls_number_restraints     1
_refine_ls_hydrogen_treatment     constr
_refine_ls_weighting_scheme     calc
_refine_ls_weighting_details
           'w = 1/[σ²(Fo²)+(0.0168P)²+15.2700P] where P=(Fo²+2Fc²)/3'
_atom_sites_solution_hydrogens     geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary     difmap
_refine_ls_shift/su_max     0.001
_refine_ls_shift/su_mean     0.000
_refine_diff_density_max     0.788
_refine_diff_density_min     -0.817
_refine_ls_extinction_method     none
_refine_ls_extinction_coef     ?
loop_
    _atom_type_symbol
    _atom_type_description
    _atom_type_scat_dispersion_real
    _atom_type_scat_dispersion_imag
    _atom_type_scat_source
    'C' 'C' 0.0033 0.0016
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
    'H' 'H' 0.0000 0.0000
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
    'Se' 'Se' -0.0929 2.2259
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
    'Nb' 'Nb' -2.0727 0.6215
                         'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
_computing_data_collection
;
COLLECT (Nonius, 1998) and DENZO (Otwinowski & Minor, 1997)
;
_computing_cell_refinement
;
COLLECT (Nonius, 1998) and DENZO (Otwinowski & Minor, 1997)
;
_computing_data_reduction
;
COLLECT (Nonius, 1998) and DENZO (Otwinowski & Minor, 1997)
;
_computing_structure_solution     'SHELXS97 (Sheldrick, 2008)'
_computing_structure_refinement     'SHELXL97 (Sheldrick, 2008)'
_computing_molecular_graphics     'ORTEPII (Johnson, 1976)'
_computing_publication_material     'SHELXL97 (Sheldrick, 2008)'
loop_
    _atom_site_type_symbol
    _atom_site_label
    _atom_site_fract_x
    _atom_site_fract_y
    _atom_site_fract_z
    _atom_site_U_iso_or_equiv
    _atom_site_adp_type
    _atom_site_calc_flag
    _atom_site_refinement_flags
    _atom_site_occupancy
    _atom_site_disorder_assembly
    _atom_site_disorder_group
    Nb Nb1 0.063734(15) 0.52132(5) 0.144254(19) 0.01341(10) Uani d . 1 . .
    Nb Nb2 0.198133(15) 0.32688(5) 0.125843(18) 0.01238(10) Uani d . 1 . .
    Se Se1 0.134400(17) 0.44206(6) 0.25388(2) 0.01579(11) Uani d . 1 . .
    Se Se2 0.134871(17) 0.52506(5) 0.12505(2) 0.01444(11) Uani d . 1 . .
    Se Se3 0.124085(18) 0.23327(6) 0.02186(2) 0.01689(12) Uani d . 1 . .
    C C1 0.11269(18) 0.3866(6) 0.3112(2) 0.0188(11) Uani d . 1 . .
    C C2 0.16075(19) 0.3821(7) 0.3716(2) 0.0288(13) Uani d . 1 . .
    H H2A 0.1827 0.2950 0.3717 0.043 Uiso calc R 1 . .
    H H2B 0.1530 0.3569 0.4022 0.043 Uiso calc R 1 . .
    H H2C 0.1772 0.4916 0.3797 0.043 Uiso calc R 1 . .
    C C3 0.07857(19) 0.5230(6) 0.3110(2) 0.0258(12) Uani d . 1 . .
    H H3A 0.0478 0.5253 0.2724 0.039 Uiso calc R 1 . .
    H H3B 0.0951 0.6325 0.3187 0.039 Uiso calc R 1 . .
    H H3C 0.0710 0.4987 0.3417 0.039 Uiso calc R 1 . .
    C C4 0.0873(2) 0.2148(6) 0.2982(2) 0.0266(12) Uani d . 1 . .
    H H4A 0.0564 0.2179 0.2597 0.040 Uiso calc R 1 . .
    H H4B 0.0799 0.1876 0.3288 0.040 Uiso calc R 1 . .
    H H4C 0.1094 0.1289 0.2978 0.040 Uiso calc R 1 . .
    C C5 0.14054(18) 0.0507(5) -0.0190(2) 0.0189(11) Uani d . 1 . .
    C C6 0.19286(18) -0.0164(6) 0.0181(2) 0.0226(12) Uani d . 1 . .
    H H6A 0.1975 -0.0653 0.0545 0.034 Uiso calc R 1 . .
    H H6B 0.2165 0.0757 0.0278 0.034 Uiso calc R 1 . .
    H H6C 0.1984 -0.1029 -0.0042 0.034 Uiso calc R 1 . .
    C C7 0.1325(2) 0.1278(6) -0.0755(2) 0.0286(13) Uani d . 1 . .
    H H7A 0.0985 0.1703 -0.0990 0.043 Uiso calc R 1 . .
    H H7B 0.1379 0.0422 -0.0982 0.043 Uiso calc R 1 . .
    H H7C 0.1558 0.2206 -0.0660 0.043 Uiso calc R 1 . .
    C C8 0.10316(19) -0.0903(6) -0.0334(2) 0.0279(13) Uani d . 1 . .
    H H8A 0.0695 -0.0456 -0.0575 0.042 Uiso calc R 1 . .
    H H8B 0.1077 -0.1366 0.0034 0.042 Uiso calc R 1 . .
    H H8C 0.1083 -0.1791 -0.0552 0.042 Uiso calc R 1 . .
    C C9 0.04568(17) 0.2209(5) 0.1467(2) 0.0169(11) Uani d . 1 . .
    H H9 0.0674 0.1508 0.1789 0.020 Uiso calc R 1 . .
    C C10 0.00674(17) 0.3205(5) 0.1427(2) 0.0175(11) Uani d . 1 . .
    H H10 -0.0017 0.3312 0.1722 0.021 Uiso calc R 1 . .
    C C11 -0.01703(18) 0.4002(6) 0.0874(2) 0.0244(12) Uani d . 1 . .
    H H11 -0.0449 0.4728 0.0722 0.029 Uiso calc R 1 . .
    C C12 0.00814(19) 0.3526(5) 0.0591(2) 0.0260(13) Uani d . 1 . .
    H H12 0.0002 0.3891 0.0210 0.031 Uiso calc RD 1 . .
    C C13 0.04664(19) 0.2436(5) 0.0952(2) 0.0217(12) Uani d . 1 . .
    H H13 0.0694 0.1939 0.0864 0.026 Uiso calc R 1 . .
    C C14 0.05650(18) 0.7993(5) 0.1043(2) 0.0169(11) Uani d . 1 . .
    H H14 0.0632 0.8145 0.0735 0.020 Uiso calc R 1 . .
    C C15 0.09097(18) 0.8104(5) 0.1654(2) 0.0165(11) Uani d . 1 . .
    H H15 0.1253 0.8348 0.1830 0.020 Uiso calc R 1 . .
    C C16 0.06628(19) 0.7796(5) 0.1961(2) 0.0220(12) Uani d . 1 . .
    H H16 0.0808 0.7806 0.2377 0.026 Uiso calc R 1 . .
    C C17 0.0164(2) 0.7471(6) 0.1541(3) 0.0258(13) Uani d . 1 . .
    H H17 -0.0088 0.7203 0.1622 0.031 Uiso calc R 1 . .
    C C18 0.01032(19) 0.7614(6) 0.0975(2) 0.0240(12) Uani d . 1 . .
    H H18 -0.0199 0.7476 0.0609 0.029 Uiso calc R 1 . .
    C C19 0.17465(18) 0.1478(5) 0.1818(2) 0.0189(11) Uani d . 1 . .
    H H19 0.1433 0.1615 0.1781 0.023 Uiso calc R 1 . .
    C C20 0.21813(18) 0.2346(6) 0.2217(2) 0.0187(11) Uani d . 1 . .
    H H20 0.2214 0.3170 0.2495 0.022 Uiso calc R 1 . .
    C C21 0.25566(19) 0.1768(6) 0.2129(2) 0.0200(11) Uani d . 1 . .
    H H21 0.2893 0.2115 0.2345 0.024 Uiso calc R 1 . .
    C C22 0.23512(17) 0.0582(5) 0.1664(2) 0.0169(11) Uani d . 1 . .
    H H22 0.2521 0.0024 0.1504 0.020 Uiso calc R 1 . .
    C C23 0.18491(18) 0.0382(5) 0.1484(2) 0.0173(11) Uani d . 1 . .
    H H23 0.1621 -0.0365 0.1188 0.021 Uiso calc R 1 . .
    C C24 0.27442(17) 0.4879(6) 0.1641(2) 0.0204(11) Uani d . 1 . .
    H H24 0.2979 0.4889 0.2053 0.024 Uiso calc R 1 . .
    C C25 0.23515(18) 0.5995(6) 0.1337(2) 0.0206(11) Uani d . 1 . .
    H H25 0.2274 0.6910 0.1505 0.025 Uiso calc R 1 . .
    C C26 0.20886(19) 0.5536(6) 0.0736(2) 0.0224(12) Uani d . 1 . .
    H H26 0.1800 0.6070 0.0430 0.027 Uiso calc R 1 . .
    C C27 0.23307(19) 0.4147(6) 0.0675(2) 0.0221(12) Uani d . 1 . .
    H H27 0.2237 0.3582 0.0317 0.027 Uiso calc R 1 . .
    C C28 0.27310(18) 0.3733(6) 0.1229(2) 0.0230(12) Uani d . 1 . .
    H H28 0.2956 0.2833 0.1313 0.028 Uiso calc R 1 . .
_geom_special_details
;
All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes)
are estimated using the full covariance matrix. The cell e.s.d.'s are taken
into account individually in the estimation of e.s.d.'s in distances, angles
and torsion angles; correlations between e.s.d.'s in cell parameters are only
used when they are defined by crystal symmetry. An approximate (isotropic)
treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s.
planes.
;
loop_
    _geom_bond_atom_site_label_1
    _geom_bond_atom_site_label_2
    _geom_bond_site_symmetry_2
    _geom_bond_distance
    _geom_bond_publ_flag
    Nb1 Se1 . 2.6630(11) y
    Nb1 Se2 . 2.5488(9) y
    Nb2 Se2 . 2.5366(7) y
    Nb2 Se3 . 2.6326(11) y
    Se1 C1 . 2.014(5) y
    Se3 C5 . 2.034(5) y
    C1 C2 . 1.532(7) n
    C1 C3 . 1.527(6) n
    C1 C4 . 1.530(6) n
    C5 C6 . 1.515(6) n
    C5 C7 . 1.514(6) n
    C5 C8 . 1.526(6) n
    Nb1 C11 . 2.390(5) ?
    Nb1 C10 . 2.391(4) ?
    Nb1 C14 . 2.411(4) ?
    Nb1 C15 . 2.417(4) ?
    Nb1 C18 . 2.420(5) ?
    Nb1 C12 . 2.422(5) ?
    Nb1 C17 . 2.436(5) ?
    Nb1 C16 . 2.450(5) ?
    Nb1 C9 . 2.465(4) ?
    Nb1 C13 . 2.477(4) ?
    Nb2 C21 . 2.387(5) ?
    Nb2 C20 . 2.395(4) ?
    Nb2 C26 . 2.402(5) ?
    Nb2 C22 . 2.405(4) ?
    Nb2 C25 . 2.421(4) ?
    Nb2 C27 . 2.422(5) ?
    Nb2 C19 . 2.434(4) ?
    Nb2 C24 . 2.436(4) ?
    Nb2 C28 . 2.438(5) ?
    Nb2 C23 . 2.462(4) ?
    C2 H2A . 0.9800 ?
    C2 H2B . 0.9800 ?
    C2 H2C . 0.9800 ?
    C3 H3A . 0.9800 ?
    C3 H3B . 0.9800 ?
    C3 H3C . 0.9800 ?
    C4 H4A . 0.9800 ?
    C4 H4B . 0.9800 ?
    C4 H4C . 0.9800 ?
    C6 H6A . 0.9800 ?
    C6 H6B . 0.9800 ?
    C6 H6C . 0.9800 ?
    C7 H7A . 0.9800 ?
    C7 H7B . 0.9800 ?
    C7 H7C . 0.9800 ?
    C8 H8A . 0.9800 ?
    C8 H8B . 0.9800 ?
    C8 H8C . 0.9800 ?
    C9 C13 . 1.392(6) ?
    C9 C10 . 1.421(6) ?
    C9 H9 . 0.9500 ?
    C10 C11 . 1.405(7) ?
    C10 H10 . 0.9500 ?
    C11 C12 . 1.400(7) ?
    C11 H11 . 0.9500 ?
    C12 C13 . 1.392(7) ?
    C12 H12 . 0.9500 ?
    C13 H13 . 0.9500 ?
    C14 C18 . 1.406(7) ?
    C14 C15 . 1.409(6) ?
    C14 H14 . 0.9500 ?
    C15 C16 . 1.411(7) ?
    C15 H15 . 0.9500 ?
    C16 C17 . 1.402(7) ?
    C16 H16 . 0.9500 ?
    C17 C18 . 1.417(7) ?
    C17 H17 . 0.9500 ?
    C18 H18 . 0.9500 ?
    C19 C23 . 1.396(6) ?
    C19 C20 . 1.405(6) ?
    C19 H19 . 0.9500 ?
    C20 C21 . 1.400(7) ?
    C20 H20 . 0.9500 ?
    C21 C22 . 1.414(6) ?
    C21 H21 . 0.9500 ?
    C22 C23 . 1.408(6) ?
    C22 H22 . 0.9500 ?
    C23 H23 . 0.9500 ?
    C24 C25 . 1.392(6) ?
    C24 C28 . 1.408(7) ?
    C24 H24 . 0.9500 ?
    C25 C26 . 1.409(7) ?
    C25 H25 . 0.9500 ?
    C26 C27 . 1.400(6) ?
    C26 H26 . 0.9500 ?
    C27 C28 . 1.390(7) ?
    C27 H27 . 0.9500 ?
    C28 H28 . 0.9500 ?
loop_
    _geom_angle_atom_site_label_1
    _geom_angle_atom_site_label_2
    _geom_angle_atom_site_label_3
    _geom_angle_site_symmetry_1
    _geom_angle_site_symmetry_3
    _geom_angle
    _geom_angle_publ_flag
    Nb2 Se2 Nb1 . . 139.76(2) y
    Se2 Nb1 Se1 . . 83.97(3) y
    Se2 Nb2 Se3 . . 84.24(3) y
    C1 Se1 Nb1 . . 117.06(14) y
    C5 Se3 Nb2 . . 115.22(14) y
    C3 C1 Se1 . . 111.0(3) y
    C4 C1 Se1 . . 111.7(3) y
    C2 C1 Se1 . . 104.7(3) y
    C6 C5 Se3 . . 113.6(3) y
    C7 C5 Se3 . . 106.3(3) y
    C8 C5 Se3 . . 106.2(3) y
    C11 Nb1 C10 . . 34.17(16) ?
    C11 Nb1 C14 . . 105.42(17) ?
    C10 Nb1 C14 . . 134.96(16) ?
    C11 Nb1 C15 . . 131.63(16) ?
    C10 Nb1 C15 . . 144.46(16) ?
    C14 Nb1 C15 . . 33.94(15) ?
    C11 Nb1 C18 . . 76.30(17) ?
    C10 Nb1 C18 . . 101.55(16) ?
    C14 Nb1 C18 . . 33.84(16) ?
    C15 Nb1 C18 . . 55.78(16) ?
    C11 Nb1 C12 . . 33.83(17) ?
    C10 Nb1 C12 . . 55.90(16) ?
    C14 Nb1 C12 . . 103.94(16) ?
    C15 Nb1 C12 . . 137.88(16) ?
    C18 Nb1 C12 . . 89.10(17) ?
    C11 Nb1 C17 . . 81.44(18) ?
    C10 Nb1 C17 . . 89.74(16) ?
    C14 Nb1 C17 . . 56.51(16) ?
    C15 Nb1 C17 . . 55.83(16) ?
    C18 Nb1 C17 . . 33.93(16) ?
    C12 Nb1 C17 . . 108.69(18) ?
    C11 Nb1 C16 . . 113.89(17) ?
    C10 Nb1 C16 . . 112.00(16) ?
    C14 Nb1 C16 . . 56.34(16) ?
    C15 Nb1 C16 . . 33.70(15) ?
    C18 Nb1 C16 . . 55.74(17) ?
    C12 Nb1 C16 . . 141.68(18) ?
    C17 Nb1 C16 . . 33.36(16) ?
    C11 Nb1 C9 . . 55.96(16) ?
    C10 Nb1 C9 . . 33.98(15) ?
    C14 Nb1 C9 . . 158.42(16) ?
    C15 Nb1 C9 . . 167.31(16) ?
    C18 Nb1 C9 . . 131.99(16) ?
    C12 Nb1 C9 . . 54.66(15) ?
    C17 Nb1 C9 . . 123.27(16) ?
    C16 Nb1 C9 . . 137.65(16) ?
    C11 Nb1 C13 . . 55.90(17) ?
    C10 Nb1 C13 . . 55.85(16) ?
    C14 Nb1 C13 . . 129.93(16) ?
    C15 Nb1 C13 . . 157.61(16) ?
    C18 Nb1 C13 . . 122.05(17) ?
    C12 Nb1 C13 . . 33.00(16) ?
    C17 Nb1 C13 . . 137.33(17) ?
    C16 Nb1 C13 . . 167.79(17) ?
    C9 Nb1 C13 . . 32.73(15) ?
    C11 Nb1 Se2 . . 129.92(13) ?
    C10 Nb1 Se2 . . 137.60(11) ?
    C14 Nb1 Se2 . . 78.08(12) ?
    C15 Nb1 Se2 . . 77.91(11) ?
    C18 Nb1 Se2 . . 109.90(13) ?
    C12 Nb1 Se2 . . 96.18(13) ?
    C17 Nb1 Se2 . . 131.82(12) ?
    C16 Nb1 Se2 . . 109.07(12) ?
    C9 Nb1 Se2 . . 104.84(11) ?
    C13 Nb1 Se2 . . 83.10(12) ?
    C11 Nb1 Se1 . . 127.43(13) ?
    C10 Nb1 Se1 . . 93.27(12) ?
    C14 Nb1 Se1 . . 122.10(11) ?
    C15 Nb1 Se1 . . 88.66(11) ?
    C18 Nb1 Se1 . . 135.43(13) ?
    C12 Nb1 Se1 . . 132.65(11) ?
    C17 Nb1 Se1 . . 105.68(14) ?
    C16 Nb1 Se1 . . 79.71(12) ?
    C9 Nb1 Se1 . . 79.41(11) ?
    C13 Nb1 Se1 . . 101.11(12) ?
    C21 Nb2 C20 . . 34.05(16) ?
    C21 Nb2 C26 . . 131.94(17) ?
    C20 Nb2 C26 . . 143.47(16) ?
    C21 Nb2 C22 . . 34.31(15) ?
    C20 Nb2 C22 . . 56.88(16) ?
    C26 Nb2 C22 . . 138.06(17) ?
    C21 Nb2 C25 . . 105.89(17) ?
    C20 Nb2 C25 . . 109.51(16) ?
    C26 Nb2 C25 . . 33.97(16) ?
    C22 Nb2 C25 . . 131.06(16) ?
    C21 Nb2 C27 . . 113.02(17) ?
    C20 Nb2 C27 . . 144.07(17) ?
    C26 Nb2 C27 . . 33.74(15) ?
    C22 Nb2 C27 . . 105.39(16) ?
    C25 Nb2 C27 . . 55.72(16) ?
    C21 Nb2 C19 . . 55.78(17) ?
    C20 Nb2 C19 . . 33.82(15) ?
    C26 Nb2 C19 . . 165.82(16) ?
    C22 Nb2 C19 . . 55.81(15) ?
    C25 Nb2 C19 . . 139.33(16) ?
    C27 Nb2 C19 . . 160.37(15) ?
    C21 Nb2 C24 . . 76.63(17) ?
    C20 Nb2 C24 . . 93.46(17) ?
    C26 Nb2 C24 . . 55.97(16) ?
    C22 Nb2 C24 . . 97.77(16) ?
    C25 Nb2 C24 . . 33.30(15) ?
    C27 Nb2 C24 . . 55.56(17) ?
    C19 Nb2 C24 . . 127.04(17) ?
    C21 Nb2 C28 . . 80.95(17) ?
    C20 Nb2 C28 . . 110.85(18) ?
    C26 Nb2 C28 . . 55.78(17) ?
    C22 Nb2 C28 . . 83.96(16) ?
    C25 Nb2 C28 . . 55.48(16) ?
    C27 Nb2 C28 . . 33.24(16) ?
    C19 Nb2 C28 . . 135.80(17) ?
    C24 Nb2 C28 . . 33.58(15) ?
    C21 Nb2 C23 . . 55.86(16) ?
    C20 Nb2 C23 . . 56.01(15) ?
    C26 Nb2 C23 . . 158.81(16) ?
    C22 Nb2 C23 . . 33.59(15) ?
    C25 Nb2 C23 . . 161.75(17) ?
    C27 Nb2 C23 . . 127.93(15) ?
    C19 Nb2 C23 . . 33.11(14) ?
    C24 Nb2 C23 . . 130.15(16) ?
    C28 Nb2 C23 . . 116.05(16) ?
    C21 Nb2 Se2 . . 121.30(12) ?
    C20 Nb2 Se2 . . 88.37(12) ?
    C26 Nb2 Se2 . . 82.81(12) ?
    C22 Nb2 Se2 . . 138.89(11) ?
    C25 Nb2 Se2 . . 77.72(11) ?
    C27 Nb2 Se2 . . 115.69(12) ?
    C19 Nb2 Se2 . . 83.15(11) ?
    C24 Nb2 Se2 . . 106.32(11) ?
    C28 Nb2 Se2 . . 132.83(11) ?
    C23 Nb2 Se2 . . 110.45(11) ?
    C21 Nb2 Se3 . . 133.43(12) ?
    C20 Nb2 Se3 . . 128.80(12) ?
    C26 Nb2 Se3 . . 85.59(12) ?
    C22 Nb2 Se3 . . 100.27(11) ?
    C25 Nb2 Se3 . . 118.04(12) ?
    C27 Nb2 Se3 . . 82.20(13) ?
    C19 Nb2 Se3 . . 94.99(12) ?
    C24 Nb2 Se3 . . 137.17(12) ?
    C28 Nb2 Se3 . . 110.99(13) ?
    C23 Nb2 Se3 . . 79.64(11) ?
    C3 C1 C4 . . 110.3(4) ?
    C3 C1 C2 . . 109.5(4) ?
    C4 C1 C2 . . 109.4(4) ?
    C1 C2 H2A . . 109.5 ?
    C1 C2 H2B . . 109.5 ?
    H2A C2 H2B . . 109.5 ?
    C1 C2 H2C . . 109.5 ?
    H2A C2 H2C . . 109.5 ?
    H2B C2 H2C . . 109.5 ?
    C1 C3 H3A . . 109.5 ?
    C1 C3 H3B . . 109.5 ?
    H3A C3 H3B . . 109.5 ?
    C1 C3 H3C . . 109.5 ?
    H3A C3 H3C . . 109.5 ?
    H3B C3 H3C . . 109.5 ?
    C1 C4 H4A . . 109.5 ?
    C1 C4 H4B . . 109.5 ?
    H4A C4 H4B . . 109.5 ?
    C1 C4 H4C . . 109.5 ?
    H4A C4 H4C . . 109.5 ?
    H4B C4 H4C . . 109.5 ?
    C6 C5 C7 . . 110.6(4) ?
    C6 C5 C8 . . 110.2(4) ?
    C7 C5 C8 . . 109.8(4) ?
    C5 C6 H6A . . 109.5 ?
    C5 C6 H6B . . 109.5 ?
    H6A C6 H6B . . 109.5 ?
    C5 C6 H6C . . 109.5 ?
    H6A C6 H6C . . 109.5 ?
    H6B C6 H6C . . 109.5 ?
    C5 C7 H7A . . 109.5 ?
    C5 C7 H7B . . 109.5 ?
    H7A C7 H7B . . 109.5 ?
    C5 C7 H7C . . 109.5 ?
    H7A C7 H7C . . 109.5 ?
    H7B C7 H7C . . 109.5 ?
    C5 C8 H8A . . 109.5 ?
    C5 C8 H8B . . 109.5 ?
    H8A C8 H8B . . 109.5 ?
    C5 C8 H8C . . 109.5 ?
    H8A C8 H8C . . 109.5 ?
    H8B C8 H8C . . 109.5 ?
    C13 C9 C10 . . 108.3(4) ?
    C13 C9 Nb1 . . 74.1(3) ?
    C10 C9 Nb1 . . 70.2(2) ?
    C13 C9 H9 . . 125.8 ?
    C10 C9 H9 . . 125.8 ?
    Nb1 C9 H9 . . 121.6 ?
    C11 C10 C9 . . 107.5(4) ?
    C11 C10 Nb1 . . 72.9(3) ?
    C9 C10 Nb1 . . 75.9(3) ?
    C11 C10 H10 . . 126.2 ?
    C9 C10 H10 . . 126.2 ?
    Nb1 C10 H10 . . 117.1 ?
    C12 C11 C10 . . 107.1(4) ?
    C12 C11 Nb1 . . 74.3(3) ?
    C10 C11 Nb1 . . 73.0(3) ?
    C12 C11 H11 . . 126.5 ?
    C10 C11 H11 . . 126.5 ?
    Nb1 C11 H11 . . 118.3 ?
    C13 C12 C11 . . 109.6(4) ?
    C13 C12 Nb1 . . 75.7(3) ?
    C11 C12 Nb1 . . 71.8(3) ?
    C13 C12 H12 . . 125.2 ?
    C11 C12 H12 . . 125.2 ?
    Nb1 C12 H12 . . 119.0 ?
    C12 C13 C9 . . 107.4(5) ?
    C12 C13 Nb1 . . 71.3(3) ?
    C9 C13 Nb1 . . 73.2(3) ?
    C12 C13 H13 . . 126.3 ?
    C9 C13 H13 . . 126.3 ?
    Nb1 C13 H13 . . 121.0 ?
    C18 C14 C15 . . 107.0(4) ?
    C18 C14 Nb1 . . 73.4(3) ?
    C15 C14 Nb1 . . 73.3(2) ?
    C18 C14 H14 . . 126.5 ?
    C15 C14 H14 . . 126.5 ?
    Nb1 C14 H14 . . 118.8 ?
    C14 C15 C16 . . 108.9(4) ?
    C14 C15 Nb1 . . 72.8(2) ?
    C16 C15 Nb1 . . 74.4(3) ?
    C14 C15 H15 . . 125.5 ?
    C16 C15 H15 . . 125.5 ?
    Nb1 C15 H15 . . 119.0 ?
    C17 C16 C15 . . 107.7(5) ?
    C17 C16 Nb1 . . 72.8(3) ?
    C15 C16 Nb1 . . 71.9(3) ?
    C17 C16 H16 . . 126.1 ?
    C15 C16 H16 . . 126.1 ?
    Nb1 C16 H16 . . 121.0 ?
    C16 C17 C18 . . 107.7(4) ?
    C16 C17 Nb1 . . 73.8(3) ?
    C18 C17 Nb1 . . 72.4(3) ?
    C16 C17 H17 . . 126.2 ?
    C18 C17 H17 . . 126.2 ?
    Nb1 C17 H17 . . 119.5 ?
    C14 C18 C17 . . 108.7(5) ?
    C14 C18 Nb1 . . 72.7(3) ?
    C17 C18 Nb1 . . 73.7(3) ?
    C14 C18 H18 . . 125.6 ?
    C17 C18 H18 . . 125.6 ?
    Nb1 C18 H18 . . 119.8 ?
    C23 C19 C20 . . 109.1(4) ?
    C23 C19 Nb2 . . 74.6(3) ?
    C20 C19 Nb2 . . 71.6(3) ?
    C23 C19 H19 . . 125.4 ?
    C20 C19 H19 . . 125.4 ?
    Nb2 C19 H19 . . 120.1 ?
    C21 C20 C19 . . 107.0(4) ?
    C21 C20 Nb2 . . 72.7(3) ?
    C19 C20 Nb2 . . 74.6(3) ?
    C21 C20 H20 . . 126.5 ?
    C19 C20 H20 . . 126.5 ?
    Nb2 C20 H20 . . 118.3 ?
    C20 C21 C22 . . 108.7(4) ?
    C20 C21 Nb2 . . 73.3(3) ?
    C22 C21 Nb2 . . 73.5(3) ?
    C20 C21 H21 . . 125.7 ?
    C22 C21 H21 . . 125.7 ?
    Nb2 C21 H21 . . 119.3 ?
    C23 C22 C21 . . 107.3(4) ?
    C23 C22 Nb2 . . 75.4(2) ?
    C21 C22 Nb2 . . 72.1(2) ?
    C23 C22 H22 . . 126.3 ?
    C21 C22 H22 . . 126.3 ?
    Nb2 C22 H22 . . 118.1 ?
    C19 C23 C22 . . 107.8(4) ?
    C19 C23 Nb2 . . 72.3(3) ?
    C22 C23 Nb2 . . 71.0(2) ?
    C19 C23 H23 . . 126.1 ?
    C22 C23 H23 . . 126.1 ?
    Nb2 C23 H23 . . 122.3 ?
    C25 C24 C28 . . 107.7(4) ?
    C25 C24 Nb2 . . 72.7(3) ?
    C28 C24 Nb2 . . 73.3(3) ?
    C25 C24 H24 . . 126.1 ?
    C28 C24 H24 . . 126.1 ?
    Nb2 C24 H24 . . 119.7 ?
    C24 C25 C26 . . 108.3(4) ?
    C24 C25 Nb2 . . 74.0(3) ?
    C26 C25 Nb2 . . 72.3(3) ?
    C24 C25 H25 . . 125.8 ?
    C26 C25 H25 . . 125.8 ?
    Nb2 C25 H25 . . 119.7 ?
    C27 C26 C25 . . 107.4(5) ?
    C27 C26 Nb2 . . 73.9(3) ?
    C25 C26 Nb2 . . 73.7(3) ?
    C27 C26 H26 . . 126.3 ?
    C25 C26 H26 . . 126.3 ?
    Nb2 C26 H26 . . 118.0 ?
    C28 C27 C26 . . 108.5(4) ?
    C28 C27 Nb2 . . 74.0(3) ?
    C26 C27 Nb2 . . 72.3(3) ?
    C28 C27 H27 . . 125.8 ?
    C26 C27 H27 . . 125.8 ?
    Nb2 C27 H27 . . 119.7 ?
    C27 C28 C24 . . 108.1(4) ?
    C27 C28 Nb2 . . 72.8(3) ?
    C24 C28 Nb2 . . 73.1(3) ?
    C27 C28 H28 . . 126.0 ?
    C24 C28 H28 . . 126.0 ?
    Nb2 C28 H28 . . 119.9 ?
data_global
_journal_data_validation_number     ?
_journal_date_recd_electronic     2008-07-14
_journal_date_accepted     2008-08-04
_journal_name_full     'Acta Crystallographica, Section C'
_journal_year     2008
_journal_volume     64
_journal_issue     10
_journal_page_first     m321
_journal_page_last     m323
_journal_paper_category     FM
_journal_coeditor_code     BM3060
_publ_contact_author_name     'Dr Andrew Hector'
_publ_contact_author_address
;
School of Chemistry
University of Southampton
Southampton SO17 1BJ
England
;
_publ_contact_author_email     a.l.hector@soton.ac.uk
_publ_contact_author_fax     ?
_publ_contact_author_phone     '023 8059 4125'
_publ_section_title
;
[{Cp₂(tBuSe)Nb}₂E}] (E = O, Se) with bridging oxide
or selenide ligands
;
loop_
    _publ_author_name
    _publ_author_address
    'Hector, Andrew L.'
;
School of Chemistry
University of Southampton
Southampton SO17 1BJ
England
;
    'Jura, Marek'
;
School of Chemistry
University of Southampton
Southampton SO17 1BJ
England
;
    'Levason, William'
;
School of Chemistry
University of Southampton
Southampton SO17 1BJ
England
;
    'Reid, Gillian'
;
School of Chemistry
University of Southampton
Southampton SO17 1BJ
England
;
    'Reid, Stuart D.'
;
School of Chemistry
University of Southampton
Southampton SO17 1BJ
England
;
    'Webster, Michael'
;
School of Chemistry
University of Southampton
Southampton SO17 1BJ
England
;
