Synthesis and Characterization of K38Nb7As24 and Cs9Nb2As6: The First Mixed-Valence Transition-Metal Zintl Phases
Franck Gascoin; Slavi C. Sevov; Inorganic Chemistry 41 (2002) 5920–5924; doi:10.1021/ic020250b

data_4318760
_publ_section_title
;
 Synthesis and Characterization of K38Nb7As24 and Cs9Nb2As6: The First
 Mixed-Valence Transition-Metal Zintl Phases
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              5920
_journal_page_last               5924
_journal_paper_doi               10.1021/ic020250b
_journal_volume                  41
_journal_year                    2002
_chemical_formula_moiety         Cs9Nb2As6
_chemical_formula_sum            'As6 Cs9 Nb2'
_chemical_formula_weight         1831.53
_chemical_name_common            Cs9Nb2As6
_chemical_name_systematic
;
   ?
;
_space_group_IT_number           61
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   17.5848(7)
_cell_length_b                   16.940(2)
_cell_length_c                   18.183(4)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      17.127
_cell_measurement_theta_min      10.045
_cell_volume                     5416.5(14)
_computing_cell_refinement       CAD4_(Enraf-Nonius,_1977)
_computing_data_collection       CAD4_(Enraf-Nonius,_1977)
_computing_data_reduction        SDS_Package_(Enraf-Nonius,_1985)
_computing_molecular_graphics    'SHELXTL (Siemens, 1994)'
_computing_publication_material  'SHELXTL (Siemens, 1994)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.863
_diffrn_measured_fraction_theta_max 0.863
_diffrn_measurement_device_type  Enraf_Nonius_CAD4
_diffrn_measurement_method       omega-2theta
_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  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0797
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       20
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       0
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            4111
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         2.01
_diffrn_standards_interval_count 200
_diffrn_standards_interval_time  120
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    20.029
_exptl_absorpt_correction_T_max  0.66529
_exptl_absorpt_correction_T_min  0.30978
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details   'average of 2 psi-scan reflections'
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    4.492
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       irregular
_exptl_crystal_F_000             6200
_exptl_crystal_size_max          0.12
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.08
_refine_diff_density_max         1.579
_refine_diff_density_min         -1.532
_refine_diff_density_rms         0.355
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.024
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     154
_refine_ls_number_reflns         4111
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.024
_refine_ls_R_factor_all          0.1066
_refine_ls_R_factor_gt           0.0563
_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^)+(0.0575P)^2^+8.2374P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1155
_refine_ls_wR_factor_ref         0.1343
_reflns_number_gt                2638
_reflns_number_total             4111
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic020250b_2.cif
_cod_data_source_block           cs9nb2as6
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_absorpt_correction_type' tag value 'psi-scans' was replaced
with 'psi-scan' value.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_original_cell_volume        5416.2(14)
_cod_database_code               4318760