Incommensurate modulations of relaxor ferroelectric Ca0.24Ba0.76Nb2O6 (CBN24) and Ca0.31Ba0.69Nb2O6 (CBN31)
Graetsch, Heribert A.; Pandey, Chandra Shehkar; Schreuer, Jürgen; Burianek, Manfred; Mühlberg, Manfred; Acta Crystallographica, Section B: Structural Science, Crystal Engineering and Materials 70 (2014) 743–749; doi:10.1107/S2052520614011676

data_2310764
_publ_section_title
;
 Incommensurate modulations of relaxor ferroelectric Ca0.24Ba0.76Nb2O6
 (CBN24) and Ca0.31Ba0.69Nb2O6 (CBN31)
;
_journal_coden_ASTM              ACSBDA
_journal_coeditor_code           DK5023
_journal_issue                   4
_journal_name_full
;
 Acta Crystallographica, Section B: Structural Science, Crystal
 Engineering and Materials
;
_journal_page_first              743
_journal_page_last               749
_journal_paper_doi               10.1107/S2052520614011676
_journal_volume                  70
_journal_year                    2014
_chemical_formula_sum            'Ba0.693 Ca0.307 Nb2 O6'
_chemical_formula_weight         389.3
_space_group_IT_number           100
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  'P 4 -2ab (x,y,1/2*z)'
_symmetry_space_group_name_H-M   'P 4 b m (a,b,2*c)'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            10
_cell_length_a                   12.4608(5)
_cell_length_b                   12.4608(5)
_cell_length_c                   7.9185(7)
_cell_measurement_reflns_used    18477
_cell_measurement_temperature    293
_cell_measurement_theta_max      36.8
_cell_measurement_theta_min      3.08
_cell_modulation_dimension       2
_cell_volume                     1229.52(13)
_computing_cell_refinement
;
CrysAlisPro, Agilent Technologies,
Version 1.171.36.24 (release 03-12-2012 CrysAlis171 .NET)
(compiled Dec  3 2012,18:21:49)
;
_computing_data_collection
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CrysAlisPro, Agilent Technologies,
Version 1.171.36.24 (release 03-12-2012 CrysAlis171 .NET)
(compiled Dec  3 2012,18:21:49)
;
_computing_data_reduction
;
CrysAlisPro, Agilent Technologies,
Version 1.171.36.24 (release 03-12-2012 CrysAlis171 .NET)
(compiled Dec  3 2012,18:21:49)
;
_diffrn_ambient_temperature      293
_diffrn_detector_area_resol_mean 8.2495
_diffrn_measured_fraction_theta_full 0.54
_diffrn_measured_fraction_theta_max 0.54
_diffrn_measurement_device       'four-cycle diffractometer'
_diffrn_measurement_device_type  'Xcalibur, Sapphire2, large Be window'
_diffrn_measurement_method       '\w and \p scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enhance (Mo) X-ray Source'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.7107
_diffrn_reflns_av_R_equivalents  0.0257
_diffrn_reflns_av_sigmaI/netI    0.0151
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -20
_diffrn_reflns_limit_index_m_1_max 1
_diffrn_reflns_limit_index_m_1_min -1
_diffrn_reflns_limit_index_m_2_max 1
_diffrn_reflns_limit_index_m_2_min -1
_diffrn_reflns_limit_k_max       20
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            52003
_diffrn_reflns_theta_full        36.33
_diffrn_reflns_theta_max         36.33
_diffrn_reflns_theta_min         2.86
_exptl_absorpt_coefficient_mu    10.366
_exptl_absorpt_correction_T_max  0.556
_exptl_absorpt_correction_T_min  0.198
_exptl_absorpt_correction_type   analytical
_exptl_absorpt_process_details
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CrysAlisPro, Agilent Technologies,
Version 1.171.36.24 (release 03-12-2012 CrysAlis171 .NET)
(compiled Dec  3 2012,18:21:49)
Analytical numeric absorption correction using a multifaceted crystal
   model based on expressions derived by R.C. Clark & J.S. Reid.
(Clark, R. C. & Reid, J. S. (1995). Acta Cryst. A51, 887-897)
;
_exptl_crystal_colour            3.08
_exptl_crystal_density_diffrn    5.2559
_exptl_crystal_description       "'3.08'"
_exptl_crystal_F_000             1750
_exptl_crystal_size_max          0.339
_exptl_crystal_size_mid          0.249
_exptl_crystal_size_min          0.09
_refine_diff_density_max         0.00
_refine_diff_density_min         -0.66
_refine_ls_abs_structure_details
'  1406 of Friedel pairs used in the refinement'
_refine_ls_abs_structure_Flack   0.47(3)
_refine_ls_extinction_coef       330(20)
_refine_ls_extinction_method
'B-C type 1 Lorentzian isotropic (Becker & Coppens, 1974)'
_refine_ls_goodness_of_fit_gt    2.11
_refine_ls_goodness_of_fit_ref   2.02
_refine_ls_number_constraints    0
_refine_ls_number_parameters     151
_refine_ls_number_reflns         2905
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0317
_refine_ls_R_factor_gt           0.0296
_refine_ls_shift/su_max          0.0261
_refine_ls_shift/su_mean         0.0021
_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          0.0459
_refine_ls_wR_factor_ref         0.0467
_reflns_number_gt                2580
_reflns_number_total             2905
_reflns_threshold_expression     I>3\s(I)
_cod_data_source_file            dk5023sup1.cif
_cod_data_source_block           cbn31
_cod_original_sg_symbol_H-M      X4bm
_cod_database_code               2310764