Refinement of the crystal structures of the tetrahedro-tetragermanides K~4~Ge~4~, Rb~4~Ge~4~ and Cs~4~Ge~4~
H. G. von Schnering; J. Llanos; J.-H. Chang; K. Peters; E.-M. Peters; R. Nesper; Zeitschrift für Kristallographie - New Crystal Structures 220 (2005) 324–326; doi:

data_8102917
_publ_section_title
;
Refinement of the crystal structures of the tetrahedro-tetragermanides 
K~4~Ge~4~, Rb~4~Ge~4~ and Cs~4~Ge~4~
;
_journal_issue                   3
_journal_name_full
'Zeitschrift f\"ur Kristallographie - New Crystal Structures'
_journal_page_first              324
_journal_page_last               326
_journal_volume                  220
_journal_year                    2005
_chemical_formula_sum            'Ge4 K4'
_chemical_formula_weight         446.833
_chemical_name_systematic
; 
 tetrapotassium tetrahedro-tetragermanide 
;
_space_group_IT_number           218
_symmetry_cell_setting           cubic
_symmetry_space_group_name_Hall  'P -4n 2 3'
_symmetry_space_group_name_H-M   'P -4 3 n'
_atom_sites_solution_hydrogens   geom
_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            8
_cell_length_a                   12.784(1)
_cell_length_b                   12.784(1)
_cell_length_c                   12.784(1)
_cell_measurement_temperature    296(2)
_cell_volume                     2089.3(3)
_computing_molecular_graphics    'ATOMS 6.0 [13]'
_computing_structure_refinement  'SHELXTL (Sheldrick, 1990) [12]'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.516
_diffrn_measured_fraction_theta_max 0.516
_diffrn_measurement_device_type  'SYNTEX P-1'
_diffrn_measurement_method       omega
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0353
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       1
_diffrn_reflns_number            432
_diffrn_reflns_theta_full        34.63
_diffrn_reflns_theta_max         34.63
_diffrn_reflns_theta_min         2.25
_exptl_absorpt_coefficient_mu    12.914
_exptl_absorpt_correction_type   psi-scan
_exptl_crystal_colour            'black shiny'
_exptl_crystal_density_diffrn    2.841
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       '{100} and {110} forms'
_exptl_crystal_F_000             1632
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.3
_exptl_crystal_size_min          0.3
_refine_diff_density_max         0.798
_refine_diff_density_min         -0.704
_refine_diff_density_rms         0.169
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.05(7)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.113
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     25
_refine_ls_number_reflns         432
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.113
_refine_ls_R_factor_all          0.0373
_refine_ls_R_factor_gt           0.0341
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0457P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0836
_refine_ls_wR_factor_ref         0.0862
_reflns_number_gt                411
_reflns_number_total             432
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            409848.cff
_cod_data_source_block           kge
_cod_database_code               8102917