Crystal structure of tetracesium octaselenidodisilicate, Cs~4~Si~2~Se~8~
B. C. Chan; P. L. Feng; Z. Hulvey; L. Polykova; R. F. Hess; K. D. Abney; P. K. Dorhout; Zeitschrift für Kristallographie - New Crystal Structures 220 (2005) 12–12; doi:

data_8102891
_publ_section_title
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Crystal structure of tetracesium octaselenidodisilicate, Cs~4~Si~2~Se~8~
;
_journal_issue                   1
_journal_name_full
'Zeitschrift f\"ur Kristallographie - New Crystal Structures'
_journal_page_first              12
_journal_page_last               12
_journal_volume                  220
_journal_year                    2005
_chemical_formula_sum            'Cs4 Se8 Si2'
_chemical_formula_weight         875.57
_chemical_name_systematic        'Tetracesium octaselenidodisilicate'
_space_group_IT_number           12
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2y'
_symmetry_space_group_name_H-M   'C 1 2/m 1'
_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                 121.833(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   15.148(3)
_cell_length_b                   7.5988(14)
_cell_length_c                   10.0568(18)
_cell_measurement_temperature    298(2)
_cell_volume                     983.5(3)
_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  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker SMART CCD'
_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  0.0243
_diffrn_reflns_av_sigmaI/netI    0.0231
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            3106
_diffrn_reflns_theta_full        23.25
_diffrn_reflns_theta_max         23.25
_diffrn_reflns_theta_min         2.38
_exptl_absorpt_coefficient_mu    14.778
_exptl_absorpt_correction_T_max  1
_exptl_absorpt_correction_T_min  0.658551
_exptl_absorpt_correction_type   SADABS
_exptl_crystal_colour            clear
_exptl_crystal_density_diffrn    2.957
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             740
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.15
_exptl_crystal_size_min          0.10
_refine_diff_density_max         1.061
_refine_diff_density_min         -0.897
_refine_diff_density_rms         0.217
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.595
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     40
_refine_ls_number_reflns         772
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.595
_refine_ls_R_factor_all          0.0301
_refine_ls_R_factor_gt           0.0278
_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^)+(0.0254P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0679
_refine_ls_wR_factor_ref         0.0683
_reflns_number_gt                720
_reflns_number_total             772
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            409815.cff
_cod_data_source_block           pdcd244
_cod_original_sg_symbol_H-M      C2/m
_cod_original_formula_sum        'Cs4 Si2 Se8'
_cod_database_code               8102891