A Niobium(V) Arsenate: Nb~9~AsO~25~
Ulutagay, Mutlu; Schimek, George L.; Hwu, Shiou-Jyh; Acta Crystallographica Section C 54 (1998) 898–900; doi:10.1107/S0108270198000134

data_2007415
_publ_section_title
;
 A Niobium(V) Arsenate: Nb~9~AsO~25~
;
_journal_issue                   7
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              898
_journal_page_last               900
_journal_paper_doi               10.1107/S0108270198000134
_journal_volume                  54
_journal_year                    1998
_chemical_formula_sum            'As Nb9 O25'
_chemical_formula_weight         1311.1
_chemical_name_systematic        'Nonaniobium arsenic pentacosaoxide,'
_space_group_IT_number           87
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  '-I 4'
_symmetry_space_group_name_H-M   'I 4/m'
_atom_type_scat_source
'International Tables for X-ray Crystallography (Vol. IV)'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   15.6684(8)
_cell_length_b                   15.6684(8)
_cell_length_c                   3.8290(10)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    298
_cell_measurement_theta_max      16.4
_cell_measurement_theta_min      12.2
_cell_volume                     940.0(3)
_computing_cell_refinement       'Siemens P3 diffractometer system'
_computing_data_collection       'Siemens P3 diffractometer system'
_computing_data_reduction        'SHELXTL-Plus (Sheldrick, 1990)'
_computing_molecular_graphics    SHELXTL-Plus
_computing_structure_refinement  SHELXTL-Plus
_computing_structure_solution    SHELXTL-Plus
_diffrn_ambient_temperature      298
_diffrn_measurement_device       'Rigaku AFC-7 diffractometer'
_diffrn_measurement_method       \w--2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         '18 kW rotating anode'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0271
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       4
_diffrn_reflns_limit_l_min       -4
_diffrn_reflns_number            1152
_diffrn_reflns_theta_max         27.50
_diffrn_reflns_theta_min         1.78
_diffrn_standards_decay_%        -0.2
_diffrn_standards_interval_count 100
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    7.149
_exptl_absorpt_correction_T_max  0.84
_exptl_absorpt_correction_T_min  0.42
_exptl_absorpt_correction_type   'empirical via \y scans (Sheldrick, 1990)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    4.632
_exptl_crystal_density_meas      ?
_exptl_crystal_description       needle
_exptl_crystal_F_000             1204
_exptl_crystal_size_max          0.120
_exptl_crystal_size_mid          0.072
_exptl_crystal_size_min          0.024
_refine_diff_density_max         0.93
_refine_diff_density_min         -1.06
_refine_ls_extinction_coef       0.00028(5)
_refine_ls_extinction_method     'Larson (1970)'
_refine_ls_goodness_of_fit_obs   1.69
_refine_ls_matrix_type           full
_refine_ls_number_constraints    0
_refine_ls_number_parameters     57
_refine_ls_number_reflns         559
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0295
_refine_ls_R_factor_obs          .0259
_refine_ls_shift/esd_max         0.001
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details     'w = 1/[\s^2^(F)+0.0005F^2^]'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.0528
_refine_ls_wR_factor_obs         .0522
_reflns_number_observed          559
_reflns_number_total             620
_reflns_observed_criterion       F>4\s(F)
_cod_data_source_file            br1199.cif
_cod_data_source_block           structure
_cod_depositor_comments
;
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 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value '1/[\s^2^(F)+0.0005F^2^]' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to 'w =
1/[\s^2^(F)+0.0005F^2^]'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_cell_volume        940.1(3)
_cod_original_sg_symbol_H-M      'I 4/m '
_cod_original_formula_sum        'Nb9 As1 O25 '
_cod_database_code               2007415