RE2MAl6Si4 (RE = Gd, Tb, Dy; M = Au, Pt): Layered Quaternary Intermetallics Featuring CaAl2Si2-Type and YNiAl4Ge2-Type Slabs Grown from Aluminum Flux
Susan E. Latturner; Daniel Bilc; S. D. Mahanti; Mercouri G. Kanatzidis; Inorganic Chemistry 42 (2003) 7959–7966; doi:10.1021/ic0346432

data_4312596
_publ_contact_author
; 
     Prof. M. G. Kanatzidis
     Department of Chemistry
     Michigan State University
     East Lansing, MI  48824    
;
_publ_contact_author_email       kanatzid@cem.msu.edu
_publ_contact_author_phone       '(517) 355-9715'
_publ_section_title
;
 RE2MAl6Si4 (RE = Gd, Tb, Dy; M = Au, Pt): Layered Quaternary
 Intermetallics Featuring CaAl2Si2-Type and YNiAl4Ge2-Type Slabs Grown
 from Aluminum Flux
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              7959
_journal_page_last               7966
_journal_paper_doi               10.1021/ic0346432
_journal_volume                  42
_journal_year                    2003
_chemical_formula_sum            'Al6 Au Gd2 Si4'
_chemical_formula_weight         785.71
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           166
_symmetry_cell_setting           rhombohedral
_symmetry_space_group_name_Hall  '-R 3 2"'
_symmetry_space_group_name_H-M   'R -3 m :H'
_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                120.00
_cell_formula_units_Z            3
_cell_length_a                   4.1749(8)
_cell_length_b                   4.1749(8)
_cell_length_c                   50.593(15)
_cell_measurement_temperature    293(2)
_cell_volume                     763.7(3)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.937
_diffrn_measured_fraction_theta_max 0.937
_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  0.0438
_diffrn_reflns_av_sigmaI/netI    0.0253
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       85
_diffrn_reflns_limit_l_min       -85
_diffrn_reflns_number            4043
_diffrn_reflns_theta_full        37.57
_diffrn_reflns_theta_max         37.57
_diffrn_reflns_theta_min         11.34
_exptl_absorpt_coefficient_mu    18.781
_exptl_crystal_density_diffrn    5.125
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             682
_refine_diff_density_max         2.352
_refine_diff_density_min         -3.324
_refine_diff_density_rms         0.316
_refine_ls_extinction_coef       0.0046(3)
_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   1.012
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     22
_refine_ls_number_reflns         561
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.012
_refine_ls_R_factor_all          0.0264
_refine_ls_R_factor_gt           0.0213
_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^)+(0.0268P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0453
_refine_ls_wR_factor_ref         0.0467
_reflns_number_gt                485
_reflns_number_total             561
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic0346432si20030609_054510_2.cif
_cod_data_source_block           2sl271h
_cod_original_sg_symbol_H-M      'R -3 m'
_cod_database_code               4312596