Crystal structure of Cr-bearing Mg~3~BeAl~8~O~16~, a new polytype of magnesiotaaffeite-2<i>N</i>'2<i>S</i>
Malcherek, Thomas; Schlüter, Jochen; Acta Crystallographica Section E 72 (2016) 1060–1063; doi:10.1107/S2056989016010215

data_2241752
_publ_section_title
;
 Crystal structure of Cr-bearing Mg~3~BeAl~8~O~16~, a new polytype of
 magnesiotaaffeite-2<i>N</i>'2<i>S</i>
;
_journal_coeditor_code           WM5296
_journal_issue                   7
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              1060
_journal_page_last               1063
_journal_paper_doi               10.1107/S2056989016010215
_journal_volume                  72
_journal_year                    2016
_chemical_formula_analytical     'Al7.86 Be Cr0.19 Mg2.93 O16'
_chemical_formula_iupac          'Mg3 Be Al8 O16'
_chemical_formula_sum            'Al7.92 Be Cr0.15 Mg2.92 O16'
_chemical_formula_weight         557.75
_chemical_name_systematic
;
Trimagnesium beryllium octaaluminium hexadecaoxide
;
_space_group_crystal_system      trigonal
_space_group_IT_number           164
_space_group_name_Hall           '-P 3 2"'
_space_group_name_H-M_alt        'P -3 m 1'
_symmetry_space_group_name_Hall  '-P 3 2"'
_symmetry_space_group_name_H-M   'P -3 m 1'
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                120
_cell_formula_units_Z            2
_cell_length_a                   5.6788(3)
_cell_length_b                   5.6788(3)
_cell_length_c                   18.3368(14)
_cell_measurement_reflns_used    9717
_cell_measurement_temperature    295(2)
_cell_measurement_theta_max      35
_cell_measurement_theta_min      2.22
_cell_volume                     512.11(5)
_computing_cell_refinement
;
<i>EVAL15</i>/<i>Peakref</i> (Schreurs <i>et al.</i>,  2010)
;
_computing_data_collection
;
COLLECT (Nonius, 1998)
;
_computing_data_reduction
;
EVAL15 (Schreurs <i>et al.</i>,  2010)
;
_computing_molecular_graphics
;
<i>VESTA</i> (Momma & Izumi, 2011)
;
_computing_publication_material
;
publCIF (Westrip, 2010)
;
_computing_structure_refinement
;
SHELXL2014 (Sheldrick, 2015)
;
_computing_structure_solution
;
SUPERFLIP (Palatinus & Chapuis, 2007)
;
_diffrn_ambient_temperature      295(2)
_diffrn_detector_area_resol_mean 9
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Nonius KappaCCD'
_diffrn_measurement_method       '\f scans, and \w scans with \k offsets'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.0395
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       29
_diffrn_reflns_limit_l_min       -29
_diffrn_reflns_number            10618
_diffrn_reflns_theta_full        25.240
_diffrn_reflns_theta_max         34.995
_diffrn_reflns_theta_min         2.221
_exptl_absorpt_coefficient_mu    1.254
_exptl_absorpt_correction_T_max  0.747
_exptl_absorpt_correction_T_min  0.614
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
(<i>SADABS</i>; Bruker, 2008)
;
_exptl_crystal_colour            red
_exptl_crystal_density_diffrn    3.617
_exptl_crystal_description       tabular
_exptl_crystal_F_000             547
_exptl_crystal_size_max          0.23
_exptl_crystal_size_mid          0.22
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.412
_refine_diff_density_min         -1.010
_refine_ls_extinction_coef       0.046(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method
;
SHELXL2014 (Sheldrick, 2015)
;
_refine_ls_goodness_of_fit_ref   0.834
_refine_ls_hydrogen_treatment    undef
_refine_ls_matrix_type           full
_refine_ls_number_parameters     75
_refine_ls_number_reflns         940
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.834
_refine_ls_R_factor_all          0.0186
_refine_ls_R_factor_gt           0.0180
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
;
w = {1-exp[-5(sin\q/\l)^2^)]}/[\s^2^(Fo^2^)+(0.0296P)^2^+0.0310P]
where P=(Fo^2^+2Fc^2^)/3
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0400
_refine_ls_wR_factor_ref         0.0404
_reflns_number_gt                912
_reflns_number_total             940
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            wm5296sup1.cif
_cod_data_source_block           I
_cod_original_cell_volume        512.11(7)
_cod_database_code               2241752
_shelx_hkl_checksum              42004
_shelx_res_checksum              11065
_cod_database_fobs_code 2241752