#------------------------------------------------------------------------------ #$Date: 2009-11-18 16:56:34 +0200 (Wed, 18 Nov 2009) $ #$Revision: 858 $ #$URL: file:///home/coder/svn-repositories/cod/cif/4/4000243.cif $ #------------------------------------------------------------------------------ # # This file is available in the Crystallography Open Database (COD), # http://www.crystallography.net/ # # All data on this site have been placed in the public domain by the # contributors. # data_4000243 _journal_name_full 'Chemistry of Materials' _journal_year 2003 _publ_section_title ; "Nanoscale Zippers" in the Crystalline Solid: Structural Variations in the Magnetocaloric Material Gd5(Si1.5Ge2.5) ; loop_ _publ_author_name 'Choe, Wonyoung' 'Miller, Gordon J.' 'Meyers, John' 'Chumbley, Scott' 'Pecharsky, A. O.' _chemical_formula_moiety 'Gd5 Si1.5 Ge2.5' _chemical_formula_sum 'Gd5 Ge2.5 Si1.5' _[local]_cod_chemical_formula_sum_orig 'Gd5 Si1.5 Ge2.5' _chemical_formula_weight 1009.86 _symmetry_cell_setting orthorhombic _symmetry_space_group_name_H-M 'P n m a' loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x+1/2, -y, z+1/2' '-x, y+1/2, -z' 'x+1/2, -y+1/2, -z+1/2' '-x, -y, -z' 'x-1/2, y, -z-1/2' 'x, -y-1/2, z' '-x-1/2, y-1/2, z-1/2' _cell_length_a 7.517(3) _cell_length_b 14.800(5) _cell_length_c 7.790(3) _cell_angle_alpha 90.00 _cell_angle_beta 90.00 _cell_angle_gamma 90.00 _cell_volume 866.6(5) _cell_formula_units_Z 4 _cell_measurement_temperature 163(2) _cell_measurement_reflns_used ? _cell_measurement_theta_min ? _cell_measurement_theta_max ? _exptl_crystal_description block _exptl_crystal_colour black _exptl_crystal_size_max 0.2 _exptl_crystal_size_mid 0.1 _exptl_crystal_size_min 0.05 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 7.569 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 1648 _exptl_absorpt_coefficient_mu 44.715 _exptl_absorpt_correction_type empirical _exptl_absorpt_correction_T_min ? _exptl_absorpt_correction_T_max ? _exptl_absorpt_process_details 'SADABS 2.01 (Sheldrick, 2000)' _diffrn_ambient_temperature 293(2) _diffrn_radiation_wavelength 0.71073 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device_type 'Bruker SMART 1000' _diffrn_measurement_method '\w scans' _diffrn_detector_area_resol_mean ? _diffrn_standards_number ? _diffrn_standards_interval_count ? _diffrn_standards_interval_time ? _diffrn_standards_decay_% 0 _diffrn_reflns_number 2011 _diffrn_reflns_av_R_equivalents 0.0522 _diffrn_reflns_av_sigmaI/netI 0.0359 _diffrn_reflns_limit_h_min -8 _diffrn_reflns_limit_h_max 4 _diffrn_reflns_limit_k_min -16 _diffrn_reflns_limit_k_max 15 _diffrn_reflns_limit_l_min -8 _diffrn_reflns_limit_l_max 8 _diffrn_reflns_theta_min 2.75 _diffrn_reflns_theta_max 23.30 _reflns_number_total 645 _reflns_number_gt 546 _reflns_threshold_expression >2sigma(I) _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.0659P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment mixed _refine_ls_extinction_method SHELXL _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_number_reflns 645 _refine_ls_number_parameters 50 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.0470 _refine_ls_R_factor_gt 0.0403 _refine_ls_wR_factor_ref 0.0971 _refine_ls_wR_factor_gt 0.0944 _refine_ls_goodness_of_fit_ref 1.035 _refine_ls_restrained_S_all 1.035 _refine_ls_shift/su_max 1.481 _refine_ls_shift/su_mean 0.030 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symmetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group Gd1 Gd 0.02221(12) 0.40335(6) 0.18236(10) 0.0072(4) Uani 1 1 d . . . Gd2 Gd 0.67909(11) 0.37729(6) 0.82311(10) 0.0065(4) Uani 1 1 d . . . Gd3 Gd 0.14941(16) 0.7500 0.50944(14) 0.0058(4) Uani 1 2 d S . . T1G Ge 0.8462(3) 0.45972(16) 0.5296(3) 0.0075(9) Uani 0.690(8) 1 d P . . T1S Si 0.8462(3) 0.45972(16) 0.5296(3) 0.0075(9) Uani 0.31 1 d P . . T2G Ge 0.0237(5) 0.7500 0.1024(4) 0.0061(14) Uani 0.526(10) 2 d SP . . T2S Si 0.0237(5) 0.7500 0.1024(4) 0.0061(14) Uani 0.47 2 d SP . . T3G Ge 0.2689(5) 0.7500 0.8707(4) 0.0058(13) Uani 0.523(10) 2 d SP . . T3S Si 0.2689(5) 0.7500 0.8707(4) 0.0058(13) Uani 0.48 2 d SP . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 Gd1 0.0078(6) 0.0119(6) 0.0018(5) -0.0003(3) 0.0012(3) -0.0010(4) Gd2 0.0071(6) 0.0107(6) 0.0018(5) -0.0002(3) 0.0003(3) 0.0000(4) Gd3 0.0064(7) 0.0097(8) 0.0014(7) 0.000 0.0000(5) 0.000 T1G 0.0104(14) 0.0115(16) 0.0006(13) 0.0014(9) 0.0004(9) -0.0017(10) T1S 0.0104(14) 0.0115(16) 0.0006(13) 0.0014(9) 0.0004(9) -0.0017(10) T2G 0.007(2) 0.010(2) 0.001(2) 0.000 -0.0001(14) 0.000 T2S 0.007(2) 0.010(2) 0.001(2) 0.000 -0.0001(14) 0.000 T3G 0.007(2) 0.010(2) 0.000(2) 0.000 -0.0009(15) 0.000 T3S 0.007(2) 0.010(2) 0.000(2) 0.000 -0.0009(15) 0.000