Reticular merohedral twinning within the La~9~Sb~5~O~5~ structure family: structure of Pr~9~Sb~5~O~5~, Sm~9~Sb~5~O~5~ and Dy~9~Sb~5~O~5~
Nuss, Jürgen; Jansen, Martin; Acta Crystallographica Section B 63 (2007) 843–849; doi:10.1107/S0108768107051282

data_2103019
_publ_section_title
;
 Reticular merohedral twinning within the La~9~Sb~5~O~5~ structure
 family: structure of Pr~9~Sb~5~O~5~, Sm~9~Sb~5~O~5~ and Dy~9~Sb~5~O~5~
;
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              843
_journal_page_last               849
_journal_paper_doi               10.1107/S0108768107051282
_journal_volume                  63
_journal_year                    2007
_chemical_formula_moiety         'Sm9 Sb5 O5'
_chemical_formula_sum            'O5 Sb5 Sm9'
_chemical_formula_weight         2041.90
_space_group_IT_number           85
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  '-P 4a'
_symmetry_space_group_name_H-M   'P 4/n :2'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   10.0341(4)
_cell_length_b                   10.0341(4)
_cell_length_c                   8.9839(3)
_cell_measurement_reflns_used    7294
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      36.79
_cell_measurement_theta_min      2.27
_cell_volume                     904.53(6)
_computing_cell_refinement       'SAINT32 (Bruker AXS)'
_computing_data_collection       'Bruker Suite (Bruker AXS)'
_computing_data_reduction        'SAINT32 (Bruker AXS)'
_computing_molecular_graphics    'ATOMS (Dowty, 2005)'
_computing_publication_material  CIFTAB
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device       '3-circle goniometer'
_diffrn_measurement_device_type  'SMART APEX II, Bruker AXS'
_diffrn_measurement_method       \w-scans
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0496
_diffrn_reflns_av_sigmaI/netI    0.0269
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            31237
_diffrn_reflns_theta_full        37.02
_diffrn_reflns_theta_max         37.02
_diffrn_reflns_theta_min         2.27
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    36.011
_exptl_absorpt_correction_T_max  0.339
_exptl_absorpt_correction_T_min  0.185
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'TWINABS (G. Sheldrick 2007)'
_exptl_crystal_colour            metallic-dark-black
_exptl_crystal_density_diffrn    7.497
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1706
_exptl_crystal_size_max          0.05
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.03
_refine_diff_density_max         2.049
_refine_diff_density_min         -1.872
_refine_ls_extinction_coef       0.00034(2)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.077
_refine_ls_matrix_type           full
_refine_ls_number_parameters     48
_refine_ls_number_reflns         4116
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.077
_refine_ls_R_factor_all          0.0436
_refine_ls_R_factor_gt           0.0289
_refine_ls_shift/su_max          0.004
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0114P)^2^+3.5785P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0531
_refine_ls_wR_factor_ref         0.0573
_reflns_number_gt                3266
_reflns_number_total             4116
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            bp5006.cif
_cod_data_source_block           sm9sb5o5
_cod_original_sg_symbol_H-M      'P 4/n'
_cod_database_code               2103019