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The novel Au-substituted Ge based I type clathrates:(K,Rb)8AuxGe46-x were obtained by solid-state reactions from Rb8-nKnAu2.7Ge43.3 composition (n =0,4,6,8).The crystal structures were determined by X-ray single-crystal and powder diffraction methods.The refined lattice parameters and composition are a =10.8203(1) (A),a =10.8174(2) (A),a =10.7956(2) (A),a =10.7850(2) (A) and a =10.7743(1) (A) for Rb8Au1.85(5)Ge44.15(5),Rb8Au2.62(2)Ge43.38(2),Rb3.90(5)K4.10(5)Au2.30(2)Ge44.70(2),Rb1.78(5)K6.22(5)Au2.21(2)Ge44.79(2) and K8Au2.24(2)Ge43.76(2) for single crystal Rb8Au2.7Ge43.3,and powders Rb8Au2.7Ge43.3,Rb4K4Au2.7Ge43.3,Rb2K6Au2.7Ge43.3,K8Au2.7Ge43.3 composition in space group Pm(-3)n,respectively.Rb8Au2.62(2)Ge43.38(2) and K8Au2.24(2)Ge43.76(2) are diamagnetic with magnetic susceptibility χ =-13.4 × 10-4 and-10.4 × 10-4 emu mol-1 at 398 K,respectively.Heat capacity reveals Einstein temperature θE =56.5(1) K and Dybe temperature θD =283.7(1) K for K8Au2.24(2)Ge43.76(2),respectively.The transport properties for Rb8Au2.62(2)Ge43.38(2) are investigated.