Modulated structure of nepheline
Friese, Karen; Grzechnik, Andrzej; Petříček, Vaclav; Schönleber, Andreas; van Smaalen, Sander; Morgenroth, Wolfgang; Acta Crystallographica Section B 67 (2011) 18–29; doi:10.1107/S0108768110050822

data_2105340
_publ_section_title
;
 Modulated structure of nepheline
;
_journal_coeditor_code           CK5042
_journal_issue                   1
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              18
_journal_page_last               29
_journal_paper_doi               10.1107/S0108768110050822
_journal_volume                  67
_journal_year                    2011
_chemical_formula_sum            'Al4 Ca0.03 K0.54 Na3.24 O16 Si4'
_chemical_formula_weight         573
_chemical_name_systematic        ' ?'
_space_group_ssg_name            X3(00\g)0
_symmetry_cell_setting           trigonal
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                120
_cell_formula_units_Z            6
_cell_length_a                   17.2889(8)
_cell_length_b                   17.2889(8)
_cell_length_c                   8.3622(10)
_cell_measurement_reflns_used    12279
_cell_measurement_temperature    293
_cell_measurement_theta_max      27.6
_cell_measurement_theta_min      1.6
_cell_modulation_dimension       1
_cell_volume                     2164.6(3)
_computing_cell_refinement       EVALCCD
_computing_data_collection       MAR
_computing_data_reduction        'EVALCCD, Jana2006'
_computing_molecular_graphics    unknown
_computing_structure_refinement  Jana2006
_computing_structure_solution    'coordinates from model'
_diffrn_ambient_temperature      293
_diffrn_measured_fraction_theta_full 0.98
_diffrn_measured_fraction_theta_max 0.96
_diffrn_measurement_device       Huber-4-circle
_diffrn_measurement_method       'rotation method?'
_diffrn_radiation_monochromator  unknown
_diffrn_radiation_source         HASYLAB/DESY
_diffrn_radiation_type           synchrotron
_diffrn_radiation_wavelength     0.4
_diffrn_reflns_av_R_equivalents  0.0834
_diffrn_reflns_av_sigmaI/netI    0.0323
_diffrn_reflns_limit_h_max       38
_diffrn_reflns_limit_h_min       -39
_diffrn_reflns_limit_index_m_1_max 1
_diffrn_reflns_limit_index_m_1_min -1
_diffrn_reflns_limit_k_max       37
_diffrn_reflns_limit_k_min       -40
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            569470
_diffrn_reflns_reduction_process
;
EVALCCD (Schreurs et. al., 2010)
Jana2006 (Petricek et.al. 2006)
;
_diffrn_reflns_theta_full        27.41
_diffrn_reflns_theta_max         27.62
_diffrn_reflns_theta_min         1.56
_exptl_absorpt_coefficient_mu    0.208
_exptl_absorpt_correction_T_max  0.9602
_exptl_absorpt_correction_T_min  0.8719
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details
'Jana2006  (Petricek, Dusek & Palatinus, 2000)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    2.6366
_exptl_crystal_description       irregular
_exptl_crystal_F_000             1695
_exptl_crystal_size_max          0.43
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.12
_refine_diff_density_max         1.50
_refine_diff_density_min         -0.74
_refine_ls_abs_structure_details
'  7433 of Friedel pairs used in the refinement'
_refine_ls_abs_structure_Flack   0.4984(8)
_refine_ls_extinction_coef       30E2(3)
_refine_ls_extinction_method
'B-C type 1 Lorentzian isotropic (Becker & Coppens, 1974)'
_refine_ls_goodness_of_fit_ref   1.73
_refine_ls_number_constraints    9
_refine_ls_number_parameters     282
_refine_ls_number_reflns         24784
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0762
_refine_ls_R_factor_gt           0.0380
_refine_ls_shift/su_max          0.0381
_refine_ls_shift/su_mean         0.0041
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details     w=1/(\s^2^(F)+0.0001F^2^)
_refine_ls_weighting_scheme      sigma
_refine_ls_wR_factor_gt          0.0479
_refine_ls_wR_factor_ref         0.0510
_reflns_number_gt                11997
_reflns_number_total             24784
_reflns_threshold_expression     I>3\s(I)
_cod_data_source_file            ck5042.cif
_cod_data_source_block           Incommensurate
_cod_database_code               2105340