K~2~SrNb~6~Cl~18~, dipotassium strontium hexaniobium octadecachloride
Duraisamy, Thirumalai; Lachgar, Abdessadek; Acta Crystallographica Section C 58 (2002) i85–i86; doi:10.1107/S010827010200687X

data_2012743
_publ_section_title
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 K~2~SrNb~6~Cl~18~, dipotassium strontium hexaniobium octadecachloride
;
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              i85
_journal_page_last               i86
_journal_paper_doi               10.1107/S010827010200687X
_journal_volume                  58
_journal_year                    2002
_chemical_formula_iupac          'K2 Sr Nb6 Cl18'
_chemical_formula_moiety         'Cl18 K2 Nb6 Sr1'
_chemical_formula_structural     'K2 Sr Nb6 Cl18'
_chemical_formula_sum            'Cl18 K2 Nb6 Sr'
_chemical_formula_weight         1361.4
_chemical_name_common            'Niobium chloride'
_chemical_name_systematic
;
Dipotassium strontium hexaniobium octadecachloride
;
_space_group_IT_number           148
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_Hall  '-R 3'
_symmetry_space_group_name_H-M   'R -3 :H'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            3
_cell_length_a                   9.3025(8)
_cell_length_b                   9.3025(8)
_cell_length_c                   25.9412(18)
_cell_measurement_reflns_used    34
_cell_measurement_temperature    273(2)
_cell_measurement_theta_max      12.50
_cell_measurement_theta_min      2.67
_cell_volume                     1944.1(3)
_computing_cell_refinement       XSCANS
_computing_data_collection       'XSCANS (Bruker, 1996)'
_computing_data_reduction        'SHELXTL (Sheldrick, 1997a)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997b)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997b)'
_diffrn_ambient_temperature      273(2)
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'Bruker P4'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'normal-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0350
_diffrn_reflns_av_sigmaI/netI    0.0449
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       36
_diffrn_reflns_limit_l_min       -36
_diffrn_reflns_number            2837
_diffrn_reflns_theta_full        30.21
_diffrn_reflns_theta_max         30.21
_diffrn_reflns_theta_min         2.36
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 297
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    6.772
_exptl_absorpt_correction_T_max  0.923
_exptl_absorpt_correction_T_min  0.554
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'via \y scan (North et al., 1968)'
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    3.488
_exptl_crystal_description       'truncated cuboctahedron'
_exptl_crystal_F_000             1884
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.22
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.762
_refine_diff_density_min         -0.745
_refine_ls_extinction_coef       0.00170(11)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL (Sheldrick, 1997a)'
_refine_ls_goodness_of_fit_ref   0.897
_refine_ls_matrix_type           full
_refine_ls_number_parameters     43
_refine_ls_number_reflns         1288
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.897
_refine_ls_R_factor_all          0.0425
_refine_ls_R_factor_gt           0.0307
_refine_ls_shift/su_max          <0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0431P)^2^] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0672
_refine_ls_wR_factor_ref         0.0725
_reflns_number_gt                1072
_reflns_number_total             1288
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            br1367.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:
'_geom_bond_publ_flag' value 'Yes' changed to 'yes' according to
'/home/saulius/struct/CIF-dictionaries/cif_core.dic' dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_geom_bond_publ_flag' value 'Yes' changed to 'yes' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      'R -3'
_cod_original_formula_sum        'Cl18 K2 Nb6 Sr1'
_cod_database_code               2012743
_cod_database_fobs_code          2012743