NASICON-type Li~2.5~K~0.16~Na~0.34~Cr~2~(PO~4~)~3~
Kouass, Salah; Boughzala, Habib; Acta Crystallographica Section E 61 (2005) i231–i233; doi:10.1107/S1600536805022269

data_2207373
_publ_section_title
;
 NASICON-type Li~2.5~K~0.16~Na~0.34~Cr~2~(PO~4~)~3~
;
_journal_coeditor_code           WM6082
_journal_issue                   11
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              i231
_journal_page_last               i233
_journal_paper_doi               10.1107/S1600536805022269
_journal_volume                  61
_journal_year                    2005
_chemical_formula_iupac          'Li2.5 Na0.34 K0.16 Cr2 (P O4)3'
_chemical_formula_structural     '(K0.16 Na0.34) Li2.50 Cr2 (P O4)3'
_chemical_formula_sum            'Cr2 K0.16 Li2.5 Na0.34 O12 P3'
_chemical_formula_weight         420.31
_chemical_name_common
'lithium sodium potassium dichromate tris(phosphate)'
_chemical_name_systematic
;
Li~2.5~Na~0.34~K~0.16~Cr~2~(PO~4~)~3~
;
_space_group_crystal_system      trigonal
_space_group_IT_number           148
_symmetry_cell_setting           hexagonal
_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
_audit_creation_method           SHELXL97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            6
_cell_length_a                   8.300(2)
_cell_length_b                   8.300(2)
_cell_length_c                   22.469(5)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      16
_cell_measurement_theta_min      10
_cell_volume                     1340.5(5)
_computing_cell_refinement       'CAD-4 EXPRESS'
_computing_data_collection
'CAD-4 EXPRESS (Duisenberg, 1992; Mac\'i\<cek & Yordanov, 1992)'
_computing_data_reduction        'XCAD4 (Harms & Wocadlo, 1995)'
_computing_molecular_graphics    'DIAMOND (Brandenburg, 1998)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(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_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0268
_diffrn_reflns_av_sigmaI/netI    0.0232
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -28
_diffrn_reflns_number            2047
_diffrn_reflns_theta_full        26.88
_diffrn_reflns_theta_max         26.88
_diffrn_reflns_theta_min         2.72
_diffrn_standards_decay_%        1
_diffrn_standards_interval_time  120
_diffrn_standards_number         2
_exptl_absorpt_coefficient_mu    3.129
_exptl_absorpt_correction_T_max  0.779
_exptl_absorpt_correction_T_min  0.644
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details   '(North <i>et al.</i>, 1968)'
_exptl_crystal_colour            green
_exptl_crystal_density_diffrn    3.124
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       hexagon
_exptl_crystal_F_000             1220
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.12
_exptl_crystal_size_min          0.08
_refine_diff_density_max         0.885
_refine_diff_density_min         -0.475
_refine_ls_extinction_coef       0.0016(4)
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 1997)'
_refine_ls_goodness_of_fit_ref   1.127
_refine_ls_matrix_type           full
_refine_ls_number_parameters     67
_refine_ls_number_reflns         648
_refine_ls_number_restraints     2
_refine_ls_restrained_S_all      1.125
_refine_ls_R_factor_all          0.0311
_refine_ls_R_factor_gt           0.0247
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0328P)^2^+7.8382P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0698
_refine_ls_wR_factor_ref         0.0716
_reflns_number_gt                572
_reflns_number_total             648
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            wm6082.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'R -3'
_cod_original_formula_sum        'Cr2 K0.16 Li2.50 Na0.34 O12 P3'
_cod_database_code               2207373
_cod_database_fobs_code          2207373