Tetrayttrium difluoride disilicate orthosilicate, Y~4~F~2~[Si~2~O~7~][SiO~4~]
Schäfer, Marion C.; Hartenbach, Ingo; Schleid, Thomas; Acta Crystallographica Section E 69 (2013) i71–; doi:10.1107/S1600536813026391

data_2238683
_publ_section_title
;
 Tetrayttrium difluoride disilicate orthosilicate,
 Y~4~F~2~[Si~2~O~7~][SiO~4~]
;
_journal_issue                   10
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              i71
_journal_paper_doi               10.1107/S1600536813026391
_journal_volume                  69
_journal_year                    2013
_chemical_formula_iupac          'Y4 F2 [Si2 O7] [Si O4]'
_chemical_formula_structural     'Y4 F2 [Si2 O7] [Si O4]'
_chemical_formula_sum            'F2 O11 Si3 Y4'
_chemical_formula_weight         653.91
_chemical_name_common            'yttrium fluoride disilicate ortho-silicate'
_chemical_name_systematic
;
Tetrayttrium difluoride disilicate orthosilicate
;
_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_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                87.418(4)
_cell_angle_beta                 85.702(4)
_cell_angle_gamma                60.854(3)
_cell_formula_units_Z            2
_cell_length_a                   6.4987(5)
_cell_length_b                   6.6196(5)
_cell_length_c                   13.2978(9)
_cell_measurement_reflns_used    5136
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      28.28
_cell_measurement_theta_min      0.41
_cell_volume                     498.19(7)
_computing_cell_refinement       'SCALEPACK (Otwinowski & Minor, 1997)'
_computing_data_collection       'COLLECT (Nonius, 1998)'
_computing_data_reduction
'SCALEPACK and DENZO (Otwinowski & Minor, 1997)'
_computing_molecular_graphics    'DIAMOND (Brandenburg, 2006)'
_computing_publication_material  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type  'Nonius KappaCCD'
_diffrn_measurement_method       '\w and \f mscans'
_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  0.1203
_diffrn_reflns_av_sigmaI/netI    0.0784
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            12473
_diffrn_reflns_theta_full        28.17
_diffrn_reflns_theta_max         28.17
_diffrn_reflns_theta_min         1.54
_exptl_absorpt_coefficient_mu    23.521
_exptl_absorpt_correction_T_max  0.463
_exptl_absorpt_correction_T_min  0.104
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details   '(<i>X-SHAPE</i>; Stoe & Cie, 1995)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    4.359
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       lath-shaped
_exptl_crystal_F_000             608
_exptl_crystal_size_max          0.098
_exptl_crystal_size_mid          0.057
_exptl_crystal_size_min          0.034
_refine_diff_density_max         1.564
_refine_diff_density_min         -1.493
_refine_ls_extinction_coef       0.0029(6)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 2008)'
_refine_ls_goodness_of_fit_ref   0.982
_refine_ls_matrix_type           full
_refine_ls_number_parameters     182
_refine_ls_number_reflns         2427
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.982
_refine_ls_R_factor_all          0.1210
_refine_ls_R_factor_gt           0.0549
_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^)+(0.0233P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0884
_refine_ls_wR_factor_ref         0.1067
_reflns_number_gt                1475
_reflns_number_total             2427
_reflns_threshold_expression     I>2sigma(I)
_cod_data_source_file            wm2768.cif
_cod_data_source_block           I
_cod_original_cell_volume        498.19(6)
_cod_database_code               2238683