Dimerization of A-α-[SiNb3W9O40]7- by pH-Controlled Formation of Individual Nb-μ-O-Nb Linkages
Gyu-Shik Kim; Huadong Zeng; Wade A. Neiwert; Jennifer J. Cowan; Donald VanDerveer; Craig L. Hill; Ira A. Weinstock; Inorganic Chemistry 42 (2003) 5537–5544; doi:10.1021/ic0341845

data_4314159
_publ_contact_author
;
    Ira A. Weinstock
    Department of Chemistry
    Emory University
    1515 Pierce Drive
    Atlanta, GA 30322
;
_publ_contact_author_email       iaweinst@wisc.edu
_publ_contact_author_fax         '404 727 6076'
_publ_contact_author_phone       '404 727 7699'
_publ_section_title
;
 Dimerization of A-\a-[SiNb3W9O40]7- by pH-Controlled Formation of
 Individual Nb-\m-O-Nb Linkages
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              5537
_journal_page_last               5544
_journal_paper_doi               10.1021/ic0341845
_journal_volume                  42
_journal_year                    2003
_chemical_formula_analytical     H2Cs8[Si2Nb6W18O78]20H2O
_chemical_formula_moiety         H2Cs8[Si2Nb6W18O78]18H2O
_chemical_formula_structural     H2Cs8[Si2Nb6W18O78]18H2O
_chemical_formula_sum            'Cs8 H38 Nb6 O96 Si2 W18'
_chemical_formula_weight         6560.30
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           63
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-C 2c 2'
_symmetry_space_group_name_H-M   'C m c m'
_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                   40.847(2)
_cell_length_b                   13.2130(7)
_cell_length_c                   16.8179(9)
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      25.0
_cell_measurement_theta_min      1.34
_cell_volume                     9076.8(8)
_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      173(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  0.1374
_diffrn_reflns_av_sigmaI/netI    0.1165
_diffrn_reflns_limit_h_max       53
_diffrn_reflns_limit_h_min       -35
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            26621
_diffrn_reflns_theta_max         28.32
_diffrn_reflns_theta_min         1.00
_exptl_absorpt_coefficient_mu    26.742
_exptl_absorpt_correction_type   SADABS
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    4.804
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    none
_exptl_crystal_description       Block
_exptl_crystal_F_000             11360
_exptl_crystal_size_max          0.16
_exptl_crystal_size_mid          0.11
_exptl_crystal_size_min          0.03
_refine_diff_density_max         3.658
_refine_diff_density_min         -4.552
_refine_diff_density_rms         0.638
_refine_ls_extinction_coef       0.000000(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   1.023
_refine_ls_goodness_of_fit_ref   1.155
_refine_ls_hydrogen_treatment    none
_refine_ls_matrix_type           full
_refine_ls_number_parameters     294
_refine_ls_number_reflns         5733
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.023
_refine_ls_restrained_S_obs      1.155
_refine_ls_R_factor_all          0.1353
_refine_ls_R_factor_gt           0.0685
_refine_ls_shift/esd_mean        0.007
_refine_ls_shift/su_max          -1.875
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0747P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.1647
_refine_ls_wR_factor_ref         0.1407
_reflns_number_gt                3370
_reflns_number_total             5733
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic0341845si20030218_022159.cif
_cod_data_source_block           hill12
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' 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 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'none' was changed to '?' - the
value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0747P)^2^+0.0000P] 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^)+(0.0747P)^2^+0.0000P] 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        9076.7(8)
_cod_original_formula_sum        'H38 Cs8 Nb6 O96 Si2 W18'
_cod_database_code               4314159