An arsenate with the α-CrPO<sub>4</sub> structure type, NaCa<sub>1-x</sub>Ni<sub>3-2x</sub>Al<sub>2x</sub>(AsO<sub>4</sub>)<sub>3</sub> (x = 0.23): crystal structure, charge-distribution and bond-valence-sum analyses.
Ben Smail, Ridha; Zid, Mohamed Faouzi; Acta crystallographica. Section C, Structural chemistry 73 (2017) 896–904; doi:10.1107/S2053229617013213

data_2311931
_publ_section_title
;
 An arsenate with the \a-CrPO<sub>4</sub> structure type,
 NaCa<sub>1-x</sub>Ni<sub>3-2x</sub>Al<sub>2x</sub>(AsO<sub>4</sub>)<sub>3</sub>
 (x = 0.23): crystal structure, charge-distribution and bond-valence-sum
 analyses.
;
_journal_coeditor_code           SK3667
_journal_issue                   'Pt 11'
_journal_name_full
'Acta crystallographica. Section C, Structural chemistry'
_journal_page_first              896
_journal_page_last               904
_journal_paper_doi               10.1107/S2053229617013213
_journal_volume                  73
_journal_year                    2017
_chemical_formula_iupac          'Na Ca0.77 Ni2.54 Al0.46 (As O4)3'
_chemical_formula_moiety         'Al0.46 As3 Ni2.54 O12, Ca0.77 Na'
_chemical_formula_structural     'Na Ca0.77 Ni2.54 Al0.46 (As O4)3'
_chemical_formula_sum            'Al0.46 As3 Ca0.77 Na Ni2.54 O12'
_chemical_formula_weight         632.15
_chemical_name_systematic
;
Sodium calcium trinickel aluminium triarsenate
;
_space_group_crystal_system      orthorhombic
_space_group_IT_number           74
_space_group_name_Hall           '-I 2b 2'
_space_group_name_H-M_alt        'I m m a'
_audit_creation_method           SHELXL-2016/4
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   10.419(2)
_cell_length_b                   13.496(2)
_cell_length_c                   6.669(2)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      14.59
_cell_measurement_theta_min      12.18
_cell_volume                     937.8(4)
_computing_cell_refinement
;
CAD-4 EXPRESS (Duisenberg, 1992; Mac\'icek & Yordanov, 1992)
;
_computing_data_collection
;
CAD-4 EXPRESS (Duisenberg, 1992; Mac\'icek & Yordanov, 1992)
;
_computing_data_reduction
;
XCAD4 (Harms & Wocadlo, 1995)
;
_computing_molecular_graphics
;
DIAMOND (Brandenburg, 2005)
;
_computing_publication_material
;
WinGX (Farrugia, 2012) and publCIF (Westrip, 2010)
;
_computing_structure_refinement
;
SHELXL2016 (Sheldrick, 2015)
;
_computing_structure_solution
;
SHELXS97 (Sheldrick, 2008)
;
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Enraf--Nonius CAD-4'
_diffrn_measurement_method       \w/2\q
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0188
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -1
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -1
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            1285
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         26.896
_diffrn_reflns_theta_min         3.019
_diffrn_standards_decay_%        1
_diffrn_standards_interval_count 120
_diffrn_standards_number         2
_exptl_absorpt_coefficient_mu    16.154
_exptl_absorpt_correction_T_max  0.8600
_exptl_absorpt_correction_T_min  0.5359
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details
;
(North <i>et al.</i>,  1968)
;
_exptl_crystal_colour            Green-Yellow
_exptl_crystal_density_diffrn    4.477
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Prism
_exptl_crystal_F_000             1194
_exptl_crystal_size_max          0.230
_exptl_crystal_size_mid          0.100
_exptl_crystal_size_min          0.090
_refine_diff_density_max         0.860
_refine_diff_density_min         -0.931
_refine_ls_extinction_coef       0.00072(13)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method
;
SHELXL-2016/4 (Sheldrick 2015)
;
_refine_ls_goodness_of_fit_ref   1.130
_refine_ls_hydrogen_treatment    undef
_refine_ls_matrix_type           full
_refine_ls_number_parameters     60
_refine_ls_number_reflns         566
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.129
_refine_ls_R_factor_all          0.0227
_refine_ls_R_factor_gt           0.0196
_refine_ls_shift/su_max          0.069
_refine_ls_shift/su_mean         0.017
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0313P)^2^+3.2165P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0565
_refine_ls_wR_factor_ref         0.0579
_reflns_number_gt                521
_reflns_number_total             566
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            sk3667sup1.cif
_cod_data_source_block           I
_cod_database_code               2311931
_shelx_estimated_absorpt_t_min   0.119
_shelx_estimated_absorpt_t_max   0.324
_shelx_hkl_checksum              19262
_shelx_res_checksum              8844