Monoclinic and Hexagonal Nepheline Structures of (Na~3/4~/K~1/4~)AlGeO~4~
Hammond, R. P.; Barbier, J.; Acta Crystallographica Section B 54 (1998) 211–220; doi:10.1107/S0108768197013177

data_2105551
_publ_section_title
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 Monoclinic and Hexagonal Nepheline Structures of (Na~3/4~/K~1/4~)AlGeO~4~
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_journal_issue                   3
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              211
_journal_page_last               220
_journal_paper_doi               10.1107/S0108768197013177
_journal_volume                  54
_journal_year                    1998
_chemical_formula_analytical     'Al0.976 Ge1.028 K0.180 Na0.777 O4'
_chemical_formula_structural     'Al0.97 Ge1.03 K0.19 Na0.78 O4'
_chemical_formula_sum            'Al0.97 Ge1.03 K0.19 Na0.78 O4'
_chemical_formula_weight         190.31
_chemical_name_systematic
;
\b-sodium potassium aluminum germanate
;
_space_group_IT_number           173
_symmetry_cell_setting           hexagonal
_symmetry_space_group_name_Hall  'P 6c'
_symmetry_space_group_name_H-M   'P 63'
_audit_creation_method           SHELXL
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            8
_cell_length_a                   10.1640(10)
_cell_length_b                   10.1640(10)
_cell_length_c                   8.540(2)
_cell_measurement_reflns_used    20
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      30
_cell_measurement_theta_min      5
_cell_volume                     764.0(2)
_computing_molecular_graphics    'SHELXTL-Plus (Sheldrick, 1991)'
_computing_structure_refinement  'SHELXL-93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS-86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measurement_device       'Siemens R3m/V diffractometer'
_diffrn_measurement_method       \q-2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           AgK\a
_diffrn_radiation_wavelength     .56086
_diffrn_reflns_av_R_equivalents  .0853
_diffrn_reflns_av_sigmaI/netI    .1496
_diffrn_reflns_limit_h_max       18
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       0
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            6480
_diffrn_reflns_theta_max         30.06
_diffrn_reflns_theta_min         1.83
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 100
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    4.477
_exptl_absorpt_correction_T_max  .752
_exptl_absorpt_correction_T_min  .644
_exptl_absorpt_correction_type   'empirical \y-scans'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    3.294
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'hexagonal prism'
_exptl_crystal_F_000             715
_exptl_crystal_size_max          .14
_exptl_crystal_size_mid          .07
_exptl_crystal_size_min          .06
_refine_diff_density_max         1.010
_refine_diff_density_min         -.893
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   .00(9)
_refine_ls_extinction_coef       .0028(3)
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_all   .709
_refine_ls_goodness_of_fit_obs   .903
_refine_ls_hydrogen_treatment    noref
_refine_ls_matrix_type           full
_refine_ls_number_parameters     90
_refine_ls_number_reflns         3060
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      .709
_refine_ls_restrained_S_obs      .903
_refine_ls_R_factor_all          .1176
_refine_ls_R_factor_obs          .0411
_refine_ls_shift/esd_max         -.001
_refine_ls_shift/esd_mean        .000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0109P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         .0665
_refine_ls_wR_factor_obs         .0560
_reflns_number_observed          1380
_reflns_number_total             3060
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            br0065.cif
_cod_data_source_block           hexagonal
_cod_depositor_comments
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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 'w =
1/[\s^2^(Fo^2^)+(0.0109P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' 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^(Fo^2^)+(0.0109P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
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_cod_database_code               2105551