Synthesis, molecular structure and chemical properties of a new tungstosilicate with an open Wells‒Dawson structure, α-[Si2W18O66]16-
Laronze, Nathalie; Marrot, Jérôme; Hervé, Gilbert; Chemical Communications (Cambridge, United Kingdom)  (2003) 2360–2361; doi:10.1039/b307276b

data_7104807
_publ_section_title
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 Synthesis, molecular structure and chemical properties of a new
 tungstosilicate with an open Wells--Dawson structure, \a-[Si2W18O66]16-
;
_journal_coden_ASTM              CHCOFS
_journal_issue                   18
_journal_name_full
;
 Chemical Communications (Cambridge, United Kingdom)
;
_journal_page_first              2360
_journal_page_last               2361
_journal_paper_doi               10.1039/b307276b
_journal_year                    2003
_chemical_formula_sum            'Co2 K12 O90 Si2 W18'
_chemical_formula_weight         5392.54
_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                66.5700(10)
_cell_angle_beta                 78.8020(10)
_cell_angle_gamma                87.0530(10)
_cell_formula_units_Z            2
_cell_length_a                   15.00330(10)
_cell_length_b                   18.2970(3)
_cell_length_c                   18.4060(2)
_cell_measurement_reflns_used    10098
_cell_measurement_temperature    296(2)
_cell_volume                     4545.98(9)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SHELXTL'
_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_measured_fraction_theta_full 0.876
_diffrn_measured_fraction_theta_max 0.876
_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  0.0482
_diffrn_reflns_av_sigmaI/netI    0.1305
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       25
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       25
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            31855
_diffrn_reflns_theta_full        29.65
_diffrn_reflns_theta_max         29.65
_diffrn_reflns_theta_min         1.21
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    23.712
_exptl_absorpt_correction_T_max  0.1631
_exptl_absorpt_correction_T_min  0.0427
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Sheldrick, 1996)'
_exptl_crystal_colour            pink
_exptl_crystal_density_diffrn    3.940
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       parallelepiped
_exptl_crystal_F_000             4724
_exptl_crystal_size_max          0.36
_exptl_crystal_size_mid          0.16
_exptl_crystal_size_min          0.12
_refine_diff_density_max         3.180
_refine_diff_density_min         -4.087
_refine_diff_density_rms         0.455
_refine_ls_extinction_coef       0.000315(11)
_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   0.934
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     1116
_refine_ls_number_reflns         22472
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.934
_refine_ls_R_factor_all          0.1049
_refine_ls_R_factor_gt           0.0494
_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^)+(0.0446P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1088
_refine_ls_wR_factor_ref         0.1232
_reflns_number_gt                12676
_reflns_number_total             22472
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b307276b.txt
_cod_data_source_block           2
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
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 
;
_cod_original_sg_symbol_H-M      P-1
_cod_database_code               7104807