Synthesis and pH-variable ultracentrifugation molecular weight measurements of the dimeric, Ti–O–Ti bridged anhydride form of a novel di-Ti^IV^-1,2-substituted α-Keggin polyoxotungstate. Molecular structure of the [(α-1,2-PW~10~Ti~2~O~39~)~2~]^10-^ polyoxoanion
Nomiya, Kenji; Takahashi, Mizuto; Widegren, Jason A.; Aizawa, Takao; Sakai, Yoshitaka; Kasuga, Noriko C.; Journal of the Chemical Society, Dalton Transactions  (2002) 3679–3685; doi:10.1039/b204775f

data_7011834
_publ_section_title
;
 Synthesis and pH-variable ultracentrifugation molecular weight
 measurements of the dimeric, Ti--O--Ti bridged anhydride form
 of a novel di-Ti^IV^-1,2-substituted \a-Keggin polyoxotungstate.
 Molecular structure of the [(\a-1,2-PW~10~Ti~2~O~39~)~2~]^10-^
 polyoxoanion
;
_journal_coden_ASTM              JCSDAA
_journal_issue                   19
_journal_name_full
'Journal of the Chemical Society, Dalton Transactions'
_journal_page_first              3679
_journal_page_last               3685
_journal_paper_doi               10.1039/b204775f
_journal_year                    2002
_chemical_compound_source        'local laboratory'
_chemical_formula_sum            'H34 K10 O95 P2 Ti4 W20'
_chemical_formula_weight         5875.81
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                103.896(10)
_cell_angle_beta                 98.175(11)
_cell_angle_gamma                77.220(9)
_cell_formula_units_Z            2
_cell_length_a                   19.052(2)
_cell_length_b                   21.021(2)
_cell_length_c                   12.7775(17)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      14.7
_cell_measurement_theta_min      13.6
_cell_volume                     4823.0(10)
_computing_cell_refinement       'MSC/AFC Diffractometer Control'
_computing_data_collection       'MSC/AFC Diffractometer Control'
_computing_data_reduction
'teXsan for Windows version 1.06(MSC, 1997-1999)'
_computing_molecular_graphics
'teXsan for Windows version 1.06(MSC,1997-1999)'
_computing_publication_material
'teXsan for Windows version 1.06(MSC,1997-1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution
'teXsan for Windows version 1.06(MSC, 1997-1999)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Rigaku AFC5S'
_diffrn_measurement_method       \w-2\q
_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  0.0308
_diffrn_reflns_av_sigmaI/netI    0.1409
_diffrn_reflns_limit_h_max       24
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       27
_diffrn_reflns_limit_k_min       -26
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            22712
_diffrn_reflns_theta_full        27.49
_diffrn_reflns_theta_max         27.49
_diffrn_reflns_theta_min         2.51
_diffrn_standards_decay_%        -1.06
_diffrn_standards_interval_count 150
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    246.3
_exptl_absorpt_correction_T_max  0.218
_exptl_absorpt_correction_T_min  1.000
_exptl_absorpt_correction_type
;
\y scans (North,Phillips & Matthews, 1968)
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    4.05
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    .
_exptl_crystal_description       needle
_exptl_crystal_F_000             5164
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.10
_refine_diff_density_max         11.261
_refine_diff_density_min         -10.601
_refine_diff_density_rms         1.082
_refine_ls_extinction_coef       0.00024(4)
_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   1.061
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     667
_refine_ls_number_reflns         22053
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.061
_refine_ls_R_factor_all          0.2125
_refine_ls_R_factor_gt           0.1092
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.2000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2694
_refine_ls_wR_factor_ref         0.3222
_reflns_number_gt                11280
_reflns_number_total             22053
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            b204775f.txt
_cod_data_source_block           B204775F
_cod_original_cell_volume        4823.1(10)
_cod_original_sg_symbol_H-M      'P -1       '
_cod_database_code               7011834