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_2105552
_publ_section_title
;
 Monoclinic and Hexagonal Nepheline Structures of (Na~3/4~/K~1/4~)AlGeO~4~
;
_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_compound_source        Synthetic
_chemical_formula_analytical     'Al Ge K0.25 Na0.75 O4'
_chemical_formula_sum            'Al Ge K0.25 Na0.75 O4'
_chemical_formula_weight         190.59
_chemical_name_systematic
;
\a-sodium potassium aluminum germanate'
;
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_audit_creation_method           SHELXL
_cell_angle_alpha                90.00
_cell_angle_beta                 119.0350(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   10.0477(4)
_cell_length_b                   8.5764(4)
_cell_length_c                   10.2118(4)
_cell_measurement_temperature    293(2)
_cell_volume                     769.39(6)
_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 J413'
_diffrn_measurement_method       'CCD area detector'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     .71073
_diffrn_reflns_av_R_equivalents  .0322
_diffrn_reflns_av_sigmaI/netI    .0521
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            4438
_diffrn_reflns_theta_max         28.27
_diffrn_reflns_theta_min         2.28
_exptl_absorpt_coefficient_mu    8.410
_exptl_absorpt_correction_T_max  .928
_exptl_absorpt_correction_T_min  .762
_exptl_absorpt_correction_type   'empirical from \y-scans'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    3.291
_exptl_crystal_density_meas      ?
_exptl_crystal_description       'Irregular prism'
_exptl_crystal_F_000             720
_exptl_crystal_size_max          .07
_exptl_crystal_size_mid          .05
_exptl_crystal_size_min          .05
_refine_diff_density_max         1.679
_refine_diff_density_min         -1.142
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   .13(2)
_refine_ls_extinction_coef       .0002(4)
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_all   1.127
_refine_ls_goodness_of_fit_obs   1.126
_refine_ls_hydrogen_treatment    noref
_refine_ls_matrix_type           full
_refine_ls_number_parameters     255
_refine_ls_number_reflns         3194
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.127
_refine_ls_restrained_S_obs      1.125
_refine_ls_R_factor_all          .0709
_refine_ls_R_factor_obs          .0554
_refine_ls_shift/esd_max         .001
_refine_ls_shift/esd_mean        .005
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0236P)^2^+14.7287P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         .1204
_refine_ls_wR_factor_obs         .1109
_reflns_number_observed          2753
_reflns_number_total             3194
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            br0065.cif
_cod_data_source_block           monoclinic
_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 'calc
w=1/[\s^2^(Fo^2^)+(0.0236P)^2^+14.7287P] 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^)+(0.0236P)^2^+14.7287P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_sg_symbol_Hall     'P 2y1'
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               2105552
_database_code_amcsd             0009904