Preparation and Characterization of a Tetranuclear and Mixed-Valence Nb(II)/Nb(III) Diamagnetic Nb4Cl12Li2(THF)8 Cluster
Maryam Tayebani; Ghazar Aharonian; Khalil Feghali; Sandro Gambarotta; Glenn P. A. Yap; Inorganic Chemistry 40 (2001) 2442–2445; doi:10.1021/ic001253w

data_4319636
_publ_section_title
;
 Preparation and Characterization of a Tetranuclear and Mixed-Valence
 Nb(II)/Nb(III) Diamagnetic Nb4Cl12Li2(THF)8 Cluster
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              2442
_journal_page_last               2445
_journal_paper_doi               10.1021/ic001253w
_journal_volume                  40
_journal_year                    2001
_chemical_formula_sum            'C32 H64 Cl12 Li2 Nb4 O8'
_chemical_formula_weight         1387.75
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_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
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 91.068(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   12.763(2)
_cell_length_b                   10.989(2)
_cell_length_c                   18.517(3)
_cell_measurement_reflns_used    'reflections from 60 data frames'
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      28.29
_cell_measurement_theta_min      1.47
_cell_volume                     2596.6(8)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SHELXTL'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.918
_diffrn_measured_fraction_theta_max 0.918
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_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  0.1479
_diffrn_reflns_av_sigmaI/netI    0.2119
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            16679
_diffrn_reflns_theta_full        28.73
_diffrn_reflns_theta_max         28.73
_diffrn_reflns_theta_min         1.96
_diffrn_standards_decay_%        <1
_diffrn_standards_number         '50 standard frames at start and end'
_exptl_absorpt_coefficient_mu    1.520
_exptl_absorpt_correction_T_max  0.801514
_exptl_absorpt_correction_T_min  0.549218
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Blessing, Acta Cryst. (1995) A51 33-38.'
_exptl_crystal_colour            red
_exptl_crystal_density_diffrn    1.775
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1388
_exptl_crystal_size_max          0.1
_exptl_crystal_size_mid          0.1
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.796
_refine_diff_density_min         -0.558
_refine_diff_density_rms         0.135
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.014
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     262
_refine_ls_number_reflns         6174
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.014
_refine_ls_R_factor_all          0.1967
_refine_ls_R_factor_gt           0.0625
_refine_ls_shift/su_max          0.017
_refine_ls_shift/su_mean         0.004
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0100P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0675
_refine_ls_wR_factor_ref         0.0809
_reflns_number_gt                2515
_reflns_number_total             6174
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic001253w.cif
_cod_data_source_block           sg132
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to the built-in table from CIF Core dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 
;
_cod_original_cell_volume        2596.6(7)
_cod_database_code               4319636