Non-merohedral twinning: from minerals to proteins
Sevvana, Madhumati; Ruf, Michael; Usón, Isabel; Sheldrick, George M.; Herbst-Irmer, Regine; Acta Crystallographica Section D Structural Biology 75 (2019) –; doi:10.1107/S2059798319010179

data_2108531
_publ_section_title
;
 Non-merohedral twinning: from minerals to proteins
;
_journal_coeditor_code           RR5182
_journal_issue                   12
_journal_name_full
'Acta Crystallographica Section D Structural Biology'
_journal_paper_doi               10.1107/S2059798319010179
_journal_volume                  75
_journal_year                    2019
_chemical_formula_sum            'Cr2 Fe0.66 Mg0.34 O4'
_chemical_formula_weight         213.22
_space_group_crystal_system      cubic
_space_group_IT_number           227
_space_group_name_Hall           '-F 4vw 2vw 3'
_space_group_name_H-M_alt        'F d -3 m :2'
_audit_creation_method           SHELXL-2018/3
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   8.321(2)
_cell_length_b                   8.321(2)
_cell_length_c                   8.321(2)
_cell_measurement_reflns_used    915
_cell_measurement_temperature    292(2)
_cell_measurement_theta_max      30.4116
_cell_measurement_theta_min      4.2496
_cell_volume                     576.1(2)
_computing_cell_refinement       'SAINT V8.38A'
_computing_data_collection       'APEX2 v2018.7-2'
_computing_data_reduction        'SAINT V8.38A'
_computing_molecular_graphics    'VESTA V3.4.6, 2011'
_computing_structure_refinement  'SHELXL-2018/3 (Sheldrick, 2018)'
_computing_structure_solution
'SHELXT(G.M.Sheldrick,Acta Cryst.(2015)A71,3-8)'
_diffrn_ambient_temperature      292(2)
_diffrn_measured_fraction_theta_full 0.974
_diffrn_measured_fraction_theta_max 0.984
_diffrn_measurement_device_type  'Bruker, D8 QUEST'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0489
_diffrn_reflns_av_unetI/netI     0.0116
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            1343
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         30.352
_diffrn_reflns_theta_min         4.242
_exptl_absorpt_coefficient_mu    10.635
_exptl_absorpt_correction_T_max  0.746051
_exptl_absorpt_correction_T_min  0.295175
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'TWINABS V2012/, 2012'
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    4.916
_exptl_crystal_description       'Spinel twin'
_exptl_crystal_F_000             810
_exptl_crystal_size_max          0.500
_exptl_crystal_size_mid          0.370
_exptl_crystal_size_min          0.250
_refine_diff_density_max         0.444
_refine_diff_density_min         -0.416
_refine_ls_extinction_coef       0.0042(8)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2018/3 (Sheldrick 2018)'
_refine_ls_goodness_of_fit_ref   1.408
_refine_ls_hydrogen_treatment    undef
_refine_ls_matrix_type           full
_refine_ls_number_parameters     9
_refine_ls_number_reflns         60
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.408
_refine_ls_R_factor_all          0.0171
_refine_ls_R_factor_gt           0.0161
_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/[\s^2^(Fo^2^)+(0.0205P)^2^+2.2027P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0434
_refine_ls_wR_factor_ref         0.0441
_reflns_number_gt                58
_reflns_number_total             60
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            rr5182sup1.cif
_cod_data_source_block           chromite_4
_cod_original_cell_volume        576.1(4)
_cod_original_sg_symbol_H-M      'F d -3 m'
_cod_database_code               2108531
_shelx_estimated_absorpt_t_min   0.076
_shelx_estimated_absorpt_t_max   0.176
_shelx_hkl_checksum              67338
_shelx_res_checksum              92870
_cod_database_fobs_code 2108531