Synthesis, X-ray structure, and hydrolytic chemistry of the highly potent antiviral polyniobotungstate A-α-[Si2Nb6W18O77]8‒
Kim, Gyu-Shik; Zeng, Huadong; Rhule, Jeffrey T.; Weinstock, Ira A.; Hill, Craig L.; Chemical Communications  (1999) 1651–; doi:10.1039/a903983j

data_7110596
_publ_section_title
;
 Synthesis, X-ray structure, and hydrolytic chemistry of the highly potent
 antiviral polyniobotungstate A-\a-[Si2Nb6W18O77]8--
;
_journal_issue                   17
_journal_name_full               'Chemical Communications'
_journal_page_first              1651
_journal_paper_doi               10.1039/a903983j
_journal_year                    1999
_chemical_formula_structural     Cs6HsiNb3W9O40.4H2O
_chemical_formula_sum            'Cs6 H9 Nb3 O44 Si W9'
_chemical_formula_weight         3471.93
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           138
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  '-P 4ac 2ac'
_symmetry_space_group_name_H-M   'P 42/n c m :2'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   21.0827(4)
_cell_length_b                   21.0827(4)
_cell_length_c                   10.4262(3)
_cell_measurement_reflns_used    270
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      336
_cell_measurement_theta_min      17
_cell_volume                     4634.24(18)
_computing_cell_refinement       'Siemens XSCANS'
_computing_data_collection       'Siemens XSCANS'
_computing_data_reduction        'Siemens SHELXTL'
_computing_molecular_graphics    'Siemens SHELXTL'
_computing_publication_material  'Siemens SHELXTL'
_computing_structure_refinement  'SHELXL-93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS-86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measurement_device       'Siemens SMART CCD'
_diffrn_measurement_method       '\w 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  0.0828
_diffrn_reflns_av_sigmaI/netI    0.0377
_diffrn_reflns_limit_h_max       28
_diffrn_reflns_limit_h_min       -28
_diffrn_reflns_limit_k_max       27
_diffrn_reflns_limit_k_min       -27
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            38780
_diffrn_reflns_theta_max         28.24
_diffrn_reflns_theta_min         1.37
_exptl_absorpt_coefficient_mu    27.726
_exptl_absorpt_correction_type   empirical
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    4.992
_exptl_crystal_description       block
_exptl_crystal_F_000             6020
_exptl_crystal_size_max          0.14
_exptl_crystal_size_mid          0.13
_exptl_crystal_size_min          0.10
_refine_diff_density_max         1.701
_refine_diff_density_min         -2.558
_refine_diff_density_rms         0.306
_refine_ls_extinction_coef       0.00018(2)
_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_all   1.037
_refine_ls_goodness_of_fit_obs   1.105
_refine_ls_hydrogen_treatment    none
_refine_ls_matrix_type           full
_refine_ls_number_parameters     171
_refine_ls_number_reflns         2940
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.049
_refine_ls_restrained_S_obs      1.106
_refine_ls_R_factor_all          0.0543
_refine_ls_R_factor_obs          0.0363
_refine_ls_shift/esd_max         0.001
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0553P)^2^+25.7031P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.0991
_refine_ls_wR_factor_obs         0.0906
_reflns_number_observed          2251
_reflns_number_total             2944
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            903983jsup1.cif
_cod_data_source_block           hill22
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Tetragonal' changed to 'tetragonal'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1891 2012-01-12 08:04:46Z andrius 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0553P)^2^+25.7031P] where P=(Fo^2^+2Fc^2^)/3'
was changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to
'w=1/[\s^2^(Fo^2^)+(0.0553P)^2^+25.7031P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_cell_volume        4634.2(2)
_cod_original_sg_symbol_H-M      P4(2)/ncm
_cod_original_formula_sum        'H9 Cs6 Nb3 O44 Si W9'
_cod_database_code               7110596