Cs~6~Nb~4~Se~22~ and K~12~Nb~6~Se~35.3~: two new compounds containing the <i>M</i>~4~<i>Q</i>~22~ building block
Krizan, Jason W.; Pulido, Sergio H.; Wehrhan, Sarah E.; Chan, Benny C.; Acta Crystallographica Section C 66 (2010) i75–i78; doi:10.1107/S0108270110017038

data_2017717
_publ_section_title
;
 Cs~6~Nb~4~Se~22~ and K~12~Nb~6~Se~35.3~: two new compounds containing
 the <i>M</i>~4~<i>Q</i>~22~ building block
;
_journal_coeditor_code           KU3024
_journal_issue                   7
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              i75
_journal_page_last               i78
_journal_paper_doi               10.1107/S0108270110017038
_journal_volume                  66
_journal_year                    2010
_chemical_formula_iupac          'Cs6 Nb4 Se22'
_chemical_formula_moiety         'Cs6 Nb4 Se22'
_chemical_formula_sum            'Cs6 Nb4 Se22'
_chemical_formula_weight         2906.22
_chemical_name_common            'caesium niobium selenide'
_chemical_name_systematic
;
Hexacaesium tetraniobium docosaselenide
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 103.8530(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   12.5887(6)
_cell_length_b                   8.5127(4)
_cell_length_c                   20.3151(10)
_cell_measurement_reflns_used    5633
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      52.098
_cell_measurement_theta_min      4.647
_cell_volume                     2113.72(18)
_computing_cell_refinement       'SAINT-Plus (Bruker, 2008)'
_computing_data_collection       'APEX2 (Bruker, 2008)'
_computing_data_reduction        'SAINT-Plus (Bruker, 2008)'
_computing_molecular_graphics    'CrystalMaker (CrystalMaker Software, 2009)'
_computing_publication_material  'APEX2 (Bruker, 2008)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker APEXII CCD'
_diffrn_measurement_method       '\w and \f'
_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  0.0654
_diffrn_reflns_av_sigmaI/netI    0.0417
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_number            35929
_diffrn_reflns_theta_full        27.47
_diffrn_reflns_theta_max         27.47
_diffrn_reflns_theta_min         1.67
_exptl_absorpt_coefficient_mu    25.095
_exptl_absorpt_correction_T_max  0.7457
_exptl_absorpt_correction_T_min  0.3471
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   '(SADABS; Bruker, 2008)'
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    4.566
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             2484
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.08
_exptl_crystal_size_min          0.06
_refine_diff_density_max         4.931
_refine_diff_density_min         -2.293
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.030
_refine_ls_matrix_type           full
_refine_ls_number_parameters     145
_refine_ls_number_reflns         4844
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.030
_refine_ls_R_factor_all          0.0618
_refine_ls_R_factor_gt           0.0377
_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^)+(0.0310P)^2^+18.3443P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0794
_refine_ls_wR_factor_ref         0.0891
_reflns_number_gt                3550
_reflns_number_total             4844
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ku3024.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2017717
_cod_database_fobs_code          2017717