Ti2Nb6O12, a Novel Niobium Oxide Cluster Compound with "Chevrel Phase" Intercluster Connectivity Type
Ekaterina V. Anokhina; Michael W. Essig; Cynthia S. Day; Abdessadek Lachgar; Journal of the American Chemical Society 121 (1999) 6827–6833; doi:10.1021/ja990759e

data_4116448
_publ_contact_author_address
;
    Department of Chemistry, 
    Wake Forest University, 
    Winston-Salem, NC 27109
;
_publ_contact_author_email       lachgar@wfu.edu
_publ_contact_author_fax         '(336) 758-4656'
_publ_contact_author_name        'Abdessadek Lachgar'
_publ_contact_author_phone       '(336) 758-4676'
_publ_section_title
;
 Ti2Nb6O12, a Novel Niobium Oxide Cluster Compound with "Chevrel Phase"
 Intercluster Connectivity Type
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              6827
_journal_page_last               6833
_journal_paper_doi               10.1021/ja990759e
_journal_volume                  121
_journal_year                    1999
_chemical_formula_sum            'Nb6 O12 Ti2'
_chemical_formula_weight         845.26
_chemical_name_systematic        'dititanium hexaniobium dodecaoxide'
_space_group_IT_number           148
_symmetry_cell_setting           rhombohedral
_symmetry_space_group_name_Hall  '-R 3'
_symmetry_space_group_name_H-M   'R -3 :H'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           'SHELXL-97 and manual editing of form.cif'
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            3
_cell_length_a                   7.9364(5)
_cell_length_b                   7.9364(5)
_cell_length_c                   14.4339(10)
_cell_measurement_reflns_used    47
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      17.46
_cell_measurement_theta_min      3.27
_cell_volume                     787.34(9)
_computing_cell_refinement       'Siemens XSCANS'
_computing_data_collection       'Siemens XSCANS'
_computing_data_reduction        'Siemens SHELXTL'
_computing_molecular_graphics    'ATOMS for Windows'
_computing_publication_material  'Siemens 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 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device       'Siemens P4'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0138
_diffrn_reflns_av_sigmaI/netI    0.0197
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -1
_diffrn_reflns_limit_k_max       1
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       1
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            795
_diffrn_reflns_theta_full        31.02
_diffrn_reflns_theta_max         31.02
_diffrn_reflns_theta_min         3.28
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 97
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    7.807
_exptl_absorpt_correction_T_max  0.9928
_exptl_absorpt_correction_T_min  0.8563
_exptl_absorpt_correction_type   empirical
_exptl_crystal_colour            'black             '
_exptl_crystal_density_diffrn    5.348
_exptl_crystal_description       'octahedron        '
_exptl_crystal_F_000             1158
_exptl_crystal_size_max          0.1
_exptl_crystal_size_mid          0.1
_exptl_crystal_size_min          0.1
_refine_diff_density_max         1.151
_refine_diff_density_min         -0.678
_refine_diff_density_rms         0.183
_refine_ls_extinction_coef       0.00271(12)
_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   1.116
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     33
_refine_ls_number_reflns         562
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.116
_refine_ls_R_factor_all          0.0219
_refine_ls_R_factor_gt           0.0180
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0165P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0342
_refine_ls_wR_factor_ref         0.0349
_reflns_number_gt                518
_reflns_number_total             562
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja990759e.cif
_cod_data_source_block           ti2nb6o12
_cod_original_sg_symbol_H-M      'R -3'
_cod_database_code               4116448