Remarkable Rare-Earth Metal Silicide Oxides with Planar Si6 Rings
Limin Wang; Zhongjia Tang; Bernd Lorenz; Arnold M. Guloy; Journal of the American Chemical Society 130 (2008) 11258–11259; doi:10.1021/ja803632x

data_4108240
_publ_section_title
;
 Remarkable Rare-Earth Metal Silicide Oxides with Planar Si6 Rings
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              11258
_journal_page_last               11259
_journal_paper_doi               10.1021/ja803632x
_journal_volume                  130
_journal_year                    2008
_chemical_formula_sum            'La10 O3 Si8'
_chemical_formula_weight         1661.82
_chemical_name_systematic
;
 ?
;
_space_group_IT_number           191
_symmetry_cell_setting           hexagonal
_symmetry_space_group_name_Hall  '-P 6 2'
_symmetry_space_group_name_H-M   'P 6/m m m'
_atom_sites_solution_hydrogens   none
_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                120.00
_cell_formula_units_Z            1
_cell_length_a                   10.975(3)
_cell_length_b                   10.975(3)
_cell_length_c                   4.6804(13)
_cell_measurement_reflns_used    1417
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      27.73
_cell_measurement_theta_min      3.71
_cell_volume                     488.2(2)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'Bruker SHELXTL'
_computing_structure_solution    'Bruker SHELXTL'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_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  0.0386
_diffrn_reflns_av_sigmaI/netI    0.0188
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       6
_diffrn_reflns_limit_l_min       -5
_diffrn_reflns_number            3005
_diffrn_reflns_theta_full        27.75
_diffrn_reflns_theta_max         27.75
_diffrn_reflns_theta_min         2.14
_exptl_absorpt_coefficient_mu    21.828
_exptl_absorpt_correction_T_max  0.9685
_exptl_absorpt_correction_T_min  0.7463
_exptl_absorpt_correction_type   empirical
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    5.652
_exptl_crystal_description       block
_exptl_crystal_F_000             706
_exptl_crystal_size_max          0.12
_exptl_crystal_size_mid          0.06
_exptl_crystal_size_min          0.04
_refine_diff_density_max         1.003
_refine_diff_density_min         -0.623
_refine_diff_density_rms         0.145
_refine_ls_extinction_coef       0.00257(16)
_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   0.996
_refine_ls_hydrogen_treatment    none
_refine_ls_matrix_type           full
_refine_ls_number_parameters     20
_refine_ls_number_reflns         269
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.996
_refine_ls_R_factor_all          0.0144
_refine_ls_R_factor_gt           0.0125
_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^)+(0.0130P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0263
_refine_ls_wR_factor_ref         0.0267
_reflns_number_gt                247
_reflns_number_total             269
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja803632x-file003_1.cif
_cod_data_source_block           La10Si8O3
_cod_original_cell_volume        488.3(2)
_cod_database_code               4108240