New Members of the Homologous Series Am[M6Se8]m[M5+nSe9+n]: The Quaternary Phases A1-xM'3-xBi11+xSe20 and A1+xM'3-2xBi7+xSe14 (A = K, Rb, Cs; M' = Sn, Pb)
Antje Mrotzek; Lykourgos Iordanidis; Mercouri G. Kanatzidis; Inorganic Chemistry 40 (2001) 6204–6211; doi:10.1021/ic010285w

data_4320562
_publ_section_title
;
 New Members of the Homologous Series Am[M6Se8]m[M5+nSe9+n]: The
 Quaternary Phases A1-xM'3-xBi11+xSe20 and A1+xM'3-2xBi7+xSe14 (A = K, Rb,
 Cs; M' = Sn, Pb)
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              6204
_journal_page_last               6211
_journal_paper_doi               10.1021/ic010285w
_journal_volume                  40
_journal_year                    2001
_chemical_formula_sum            'Bi14.8 K2.8 Se28 Sn4.4'
_chemical_formula_weight         5935.50
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           11
_symmetry_space_group_name_Hall  '-P 2yb'
_symmetry_space_group_name_H-M   'P 1 21/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                 109.524(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            1
_cell_length_a                   17.402(2)
_cell_length_b                   4.2054(6)
_cell_length_c                   21.227(3)
_cell_measurement_temperature    298(2)
_cell_volume                     1464.1(3)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_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  0.0610
_diffrn_reflns_av_sigmaI/netI    0.0557
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -22
_diffrn_reflns_limit_k_max       5
_diffrn_reflns_limit_k_min       -5
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            13542
_diffrn_reflns_theta_full        27.11
_diffrn_reflns_theta_max         27.11
_diffrn_reflns_theta_min         1.85
_exptl_absorpt_coefficient_mu    63.734
_exptl_crystal_colour            silver
_exptl_crystal_density_diffrn    6.732
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             2454
_refine_diff_density_max         4.090
_refine_diff_density_min         -2.965
_refine_diff_density_rms         0.432
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.195
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     167
_refine_ls_number_reflns         3680
_refine_ls_number_restraints     9
_refine_ls_restrained_S_all      1.195
_refine_ls_R_factor_all          0.0575
_refine_ls_R_factor_gt           0.0356
_refine_ls_shift/su_max          0.426
_refine_ls_shift/su_mean         0.047
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0086P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0609
_refine_ls_wR_factor_ref         0.0640
_reflns_number_gt                2688
_reflns_number_total             3680
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic010285w_1.cif
_cod_data_source_block           K1.40Sn2.20Bi7.40Se14
_cod_original_cell_volume        1464.1(4)
_cod_original_formula_sum        'Bi14.80 K2.80 Se28 Sn4.40'
_cod_database_code               4320562