Cation vacancy order in the K0.8+xFe1.6−ySe2 system: Five-fold cell expansion accommodates 20% tetrahedral vacancies
Bacsa, J.; Ganin, A. Y.; Takabayashi, Y.; Christensen, K. E.; Prassides, K.; Rosseinsky, M. J.; Claridge, J. B.; Chemical Science 2 (2011) 1054–; doi:10.1039/c1sc00070e

data_1515542
_publ_section_title
;
 Cation vacancy order in the K0.8+xFe1.6&#x2212;ySe2 system: Five-fold
 cell expansion accommodates 20% tetrahedral vacancies
;
_journal_issue                   6
_journal_name_full               'Chemical Science'
_journal_page_first              1054
_journal_paper_doi               10.1039/c1sc00070e
_journal_volume                  2
_journal_year                    2011
_chemical_formula_sum            'Fe15.29 K9.223 Se20'
_chemical_formula_weight         2793.7
_space_group_IT_number           87
_symmetry_cell_setting           tetragonal
_symmetry_Int_Tables_number      87
_symmetry_space_group_name_Hall  '-I 4'
_symmetry_space_group_name_H-M   'I 4/m'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            1
_cell_length_a                   8.7788(4)
_cell_length_b                   8.7788(4)
_cell_length_c                   13.8604(6)
_cell_measurement_reflns_used    9913
_cell_measurement_temperature    100
_cell_measurement_theta_max      45.09
_cell_measurement_theta_min      2.32
_cell_volume                     1068.18(8)
_computing_cell_refinement       'SAINT v7.68A (Bruker, 2009)'
_computing_data_collection
'CrystalClear-SM Expert 2.0 r5 (Rigaku, 2010)'
_computing_data_reduction        'SAINT v7.68A (Bruker, 2009)'
_computing_molecular_graphics    unknown
_computing_structure_solution    unknown
_diffrn_ambient_temperature      100
_diffrn_measured_fraction_theta_full 0.98
_diffrn_measured_fraction_theta_max 0.97
_diffrn_measurement_device_type  'Rigaku AFC12 (Right) with Saturn724+ CCD'
_diffrn_measurement_method       '\w scans with a narrow frame width'
_diffrn_radiation_monochromator  'Confocal Optics'
_diffrn_radiation_source         'Rotating Anode'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_sigmaI/netI    0.071
_diffrn_reflns_limit_h_max       18
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -28
_diffrn_reflns_number            38226
_diffrn_reflns_theta_full        50
_diffrn_reflns_theta_max         50.11
_diffrn_reflns_theta_min         2.75
_exptl_absorpt_coefficient_mu    22.959
_exptl_absorpt_correction_T_max  0.1385
_exptl_absorpt_correction_T_min  0.0216
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details   'SADABS V2008-1 (Sheldrick, 2008)'
_exptl_crystal_colour            Black
_exptl_crystal_colour_lustre     metallic
_exptl_crystal_density_diffrn    4.3415
_exptl_crystal_F_000             1253
_exptl_crystal_size_max          0.13
_exptl_crystal_size_mid          0.12
_exptl_crystal_size_min          0.05
_refine_diff_density_max         2.38
_refine_diff_density_min         -1.75
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_gt    1.80
_refine_ls_goodness_of_fit_ref   1.71
_refine_ls_number_constraints    0
_refine_ls_number_parameters     35
_refine_ls_number_reflns         13772
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0721
_refine_ls_R_factor_gt           0.0578
_refine_ls_shift/su_max          0.0289
_refine_ls_shift/su_mean         0.0046
_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          0.0771
_refine_ls_wR_factor_ref         0.0849
_reflns_number_gt                10194
_reflns_number_total             13772
_reflns_threshold_expression     I>3\s(I)
_cod_data_source_file            c1sc00070e.txt
_cod_data_source_block           crystal2_JB
_cod_database_code               1515542