An aqueous route to [Ta6O19]8- and solid-state studies of isostructural niobium and tantalum oxide complexes.
Anderson, Travis M.; Rodriguez, Mark A.; Bonhomme, François; Bixler, Joel N.; Alam, Todd M.; Nyman, May; Dalton transactions (Cambridge, England : 2003)  (2007) 4517–4522; doi:10.1039/b707636c

data_7005979
_publ_section_title
;
 An aqueous route to [Ta6O19]8- and solid-state studies of
 isostructural niobium and tantalum oxide complexes.
;
_journal_issue                   40
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              4517
_journal_page_last               4522
_journal_paper_doi               10.1039/b707636c
_journal_year                    2007
_chemical_formula_moiety         '2(H Nb6 O19) (14 Na) (30 H2O)'
_chemical_formula_sum            'H62 Na14 Nb12 O68'
_chemical_formula_weight         2587.28
_chemical_name_common            'heptasodium hexaniobate'
_space_group_IT_number           58
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2n 2'
_symmetry_space_group_name_H-M   'P m n n'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            1
_cell_length_a                   10.0632(5)
_cell_length_b                   12.1301(7)
_cell_length_c                   12.6705(7)
_cell_measurement_temperature    173(2)
_cell_volume                     1546.66(15)
_computing_cell_refinement       'SMART 5.054 (Bruker, 1998)'
_computing_data_collection       'SMART 5.054 (Bruker, 1998)'
_computing_data_reduction        'SAINT+ 6.22 (Bruker, 2001)'
_computing_molecular_graphics    'SHELXTL 6.10 (Bruker, 2000)'
_computing_publication_material  'SHELXTL 6.10 (Bruker, 2000)'
_computing_structure_refinement  'XSHELL 4.02 (Bruker, 2000)'
_computing_structure_solution    SIR97
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker AXS Smart-CCD'
_diffrn_measurement_method       'omega and phi scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.0214
_diffrn_reflns_av_sigmaI/netI    0.0133
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            10764
_diffrn_reflns_theta_full        25.26
_diffrn_reflns_theta_max         25.26
_diffrn_reflns_theta_min         2.32
_exptl_absorpt_coefficient_mu    2.369
_exptl_absorpt_correction_T_max  0.8240
_exptl_absorpt_correction_T_min  0.5178
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'SADABS (Sheldrick, 1999)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    2.778
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       rod
_exptl_crystal_F_000             1252
_exptl_crystal_size_max          0.32
_exptl_crystal_size_mid          0.09
_exptl_crystal_size_min          0.09
_refine_diff_density_max         0.417
_refine_diff_density_min         -0.473
_refine_diff_density_rms         0.124
_refine_ls_extinction_coef       0.00239(17)
_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   1.217
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     150
_refine_ls_number_reflns         1489
_refine_ls_number_restraints     9
_refine_ls_restrained_S_all      1.215
_refine_ls_R_factor_all          0.0173
_refine_ls_R_factor_gt           0.0165
_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^)+(0.0260P)^2^+1.3250P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0479
_refine_ls_wR_factor_ref         0.0483
_reflns_number_gt                1447
_reflns_number_total             1489
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b707636c.txt
_cod_data_source_block           HNa7Nb6
_cod_original_sg_symbol_Hall     '-P 2n 2 '
_cod_database_code               7005979