Tripodal Tetrahedral Titanium Coordination in the Silica-Grafted Titania Epoxidation Catalysts: Is Not It Only a Myth? Selective Formation of [Cy7Si7O12Ti]2(μ-OR)2(μ-ROH) Cores on Thermal "Dissociation" of Alkoxytitanasilsesquioxanes
Olle Viotti; Gulaim A. Seisenbaeva; Vadim G. Kessler; Inorganic Chemistry 48 (2009) 9063–9065; doi:10.1021/ic901503y

data_4303348
_publ_section_title
;
Tripodal Tetrahedral Titanium Coordination in the Silica-Grafted Titania
Epoxidation Catalysts: Is Not It Only a Myth? Selective Formation of
[Cy7Si7O12Ti]2(\m-OR)2(\m-ROH) Cores on Thermal "Dissociation" of
Alkoxytitanasilsesquioxanes
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              9063
_journal_page_last               9065
_journal_paper_doi               10.1021/ic901503y
_journal_volume                  48
_journal_year                    2009
_chemical_formula_sum            'C99 H176 O27 Si14 Ti2'
_chemical_formula_weight         2287.46
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           34
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2 -2n'
_symmetry_space_group_name_H-M   'P n n 2'
_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            2
_cell_length_a                   17.087(3)
_cell_length_b                   25.441(5)
_cell_length_c                   14.559(3)
_cell_measurement_reflns_used    661(I>2sigma(I))
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      19.00
_cell_measurement_theta_min      1.61
_cell_volume                     6329(2)
_computing_cell_refinement       'Bruker SAINTPLUS'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINTPLUS'
_computing_molecular_graphics    'Bruker SHELXTL-NT'
_computing_publication_material  'Bruker SHELXTL-NT'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'Bruker SMART CCD 1k'
_diffrn_measurement_method       'Bruker SMART'
_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  0.1298
_diffrn_reflns_av_sigmaI/netI    0.1409
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       23
_diffrn_reflns_limit_k_min       -23
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            15839
_diffrn_reflns_theta_full        19.00
_diffrn_reflns_theta_max         19.00
_diffrn_reflns_theta_min         1.44
_exptl_absorpt_coefficient_mu    0.322
_exptl_absorpt_correction_T_max  0.9239
_exptl_absorpt_correction_T_min  0.8820
_exptl_absorpt_correction_type   Semi-Empirical
_exptl_absorpt_process_details   'Bruker SADABS'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.200
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    .
_exptl_crystal_description       block
_exptl_crystal_F_000             2452
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.35
_exptl_crystal_size_min          0.25
_refine_diff_density_max         0.529
_refine_diff_density_min         -0.438
_refine_diff_density_rms         0.096
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.23(16)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.190
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     620
_refine_ls_number_reflns         4876
_refine_ls_number_restraints     630
_refine_ls_restrained_S_all      1.156
_refine_ls_R_factor_all          0.1860
_refine_ls_R_factor_gt           0.1327
_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^)+(0.0881P)^2^+62.7596P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2764
_refine_ls_wR_factor_ref         0.2954
_reflns_number_gt                3334
_reflns_number_total             4876
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic901503y_si_001_1.cif
_cod_data_source_block           tisipr1
_cod_depositor_comments
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The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 
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_cod_database_code               4303348