{Ta12}/{Ta16} Cluster-Containing Polytantalotungstates with Remarkable Photocatalytic H2 Evolution Activity
Shujun Li; Shumei Liu; Shuxia Liu; Yiwei Liu; Qun Tang; Zhan Shi; Shuxin Ouyang; Jinhua Ye; Journal of the American Chemical Society 134 (2012) 19716–19721; doi:10.1021/ja307484a

data_4118944
_publ_section_title
;
 {Ta12}/{Ta16} Cluster-Containing Polytantalotungstates with Remarkable
 Photocatalytic H2 Evolution Activity
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              19716
_journal_page_last               19721
_journal_paper_doi               10.1021/ja307484a
_journal_volume                  134
_journal_year                    2012
_chemical_formula_sum            'Cs3 H18.5 K3.5 O52 Si Ta3 W9'
_chemical_formula_weight         3611.6653
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           166
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_Hall  '-R 3 2"'
_symmetry_space_group_name_H-M   'R -3 m :H'
_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                120.00
_cell_formula_units_Z            6
_cell_length_a                   18.245(9)
_cell_length_b                   18.245(9)
_cell_length_c                   27.490(16)
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      0.001
_cell_measurement_theta_min      0.006
_cell_volume                     7925(7)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SMART'
_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      296(2)
_diffrn_detector_area_resol_mean '100x100 microns'
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_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  0.1092
_diffrn_reflns_av_sigmaI/netI    0.0537
_diffrn_reflns_limit_h_max       19
_diffrn_reflns_limit_h_min       -21
_diffrn_reflns_limit_k_max       21
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       32
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            13436
_diffrn_reflns_theta_full        25.09
_diffrn_reflns_theta_max         25.09
_diffrn_reflns_theta_min         1.49
_diffrn_standards_decay_%        none
_diffrn_standards_interval_count none
_diffrn_standards_interval_time  none
_diffrn_standards_number         none
_exptl_absorpt_coefficient_mu    28.130
_exptl_absorpt_correction_T_max  0.007
_exptl_absorpt_correction_T_min  0.001
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'ABSCOR by T.Higashi 8 March, 1995'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    4.541
_exptl_crystal_description       lump
_exptl_crystal_F_000             9027
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.18
_refine_diff_density_max         2.597
_refine_diff_density_min         -2.642
_refine_diff_density_rms         0.447
_refine_ls_extinction_coef       0.000100(8)
_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   1.101
_refine_ls_matrix_type           full
_refine_ls_number_parameters     151
_refine_ls_number_reflns         1737
_refine_ls_number_restraints     48
_refine_ls_restrained_S_all      1.095
_refine_ls_R_factor_all          0.0528
_refine_ls_R_factor_gt           0.0458
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0580P)^2^+732.8701P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1213
_refine_ls_wR_factor_ref         0.1246
_reflns_number_gt                1505
_reflns_number_total             1737
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja307484a_si_002_2.cif
_cod_data_source_block           3
_cod_original_sg_symbol_H-M      'R -3 m'
_cod_original_formula_sum        'Cs3 H18.5 K3.5 O52 Si1 Ta3 W9 '
_cod_database_code               4118944