"Nanoscale Zippers" in the Crystalline Solid: Structural Variations in the Magnetocaloric Material Gd5(Si1.5Ge2.5)
Choe, Wonyoung; Miller, Gordon J.; Meyers, John; Chumbley, Scott; Pecharsky, A. O.; Chemistry of Materials  (2003) –; doi:10.1021/cm020928l

data_4000243
_publ_section_title
;
"Nanoscale Zippers" in the Crystalline Solid: Structural
Variations in the Magnetocaloric Material Gd5(Si1.5Ge2.5)
;
_journal_name_full               'Chemistry of Materials'
_journal_paper_doi               10.1021/cm020928l
_journal_year                    2003
_chemical_formula_moiety         'Gd5 Si1.5 Ge2.5'
_chemical_formula_sum            'Gd5 Ge2.5 Si1.5'
_chemical_formula_weight         1009.86
_space_group_IT_number           62
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2n'
_symmetry_space_group_name_H-M   'P n m a'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.517(3)
_cell_length_b                   14.800(5)
_cell_length_c                   7.790(3)
_cell_measurement_reflns_used    ?
_cell_measurement_temperature    163(2)
_cell_measurement_theta_max      ?
_cell_measurement_theta_min      ?
_cell_volume                     866.6(5)
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean ?
_diffrn_measurement_device_type  'Bruker SMART 1000'
_diffrn_measurement_method       '\w scans'
_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  0.0522
_diffrn_reflns_av_sigmaI/netI    0.0359
_diffrn_reflns_limit_h_max       4
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            2011
_diffrn_reflns_theta_max         23.30
_diffrn_reflns_theta_min         2.75
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count ?
_diffrn_standards_interval_time  ?
_diffrn_standards_number         ?
_exptl_absorpt_coefficient_mu    44.715
_exptl_absorpt_correction_T_max  ?
_exptl_absorpt_correction_T_min  ?
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'SADABS 2.01 (Sheldrick, 2000)'
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    7.569
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1648
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.1
_exptl_crystal_size_min          0.05
_refine_ls_extinction_coef       0.00023(10)
_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   1.035
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     50
_refine_ls_number_reflns         645
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.035
_refine_ls_R_factor_all          0.0470
_refine_ls_R_factor_gt           0.0403
_refine_ls_shift/su_max          1.481
_refine_ls_shift/su_mean         0.030
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0659P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0944
_refine_ls_wR_factor_ref         0.0971
_reflns_number_gt                546
_reflns_number_total             645
_reflns_threshold_expression     >2sigma(I)
_cod_original_formula_sum        'Gd5 Si1.5 Ge2.5'
_cod_database_code               4000243