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Type I clathrates with noble transition metal Ba₈TM₆Ge₄₀ (TM=Cu, Ag, and Au) have been investigated by inelastic neutron scattering, single crystal and synchrotron powder x-ray diffraction and DFT calculations to probe the structure and dynamics on the atomic scale. The DFT calculation assists in the assignment of the measured low energy phonon modes, and fair agreement is obtained between experiment and theory for the phonon density of states. The Cu compound shows good agreement, whereas the Ag and Au compounds show some discrepancies. Overall, the data show that the guest atom dynamics are similar in all samples. Physical property characterization was carried out on pellets pressed by spark plasma sintering. The transport properties show large differences with Ba8Cu6Ge40 being an n-type semiconductor, whereas Ba₈Ag₆Ge₄₀ and Ba₈Au₆Ge₄₀ are p-type semiconducting and metallic, respectively. The thermal conductivity was found to depend strongly on the charge carrier type. Thus, Ba₈Cu₆Ge₄₀ has a crystal-like thermal conductivity while Ba₈Ag₆Ge₄₀ and Ba₈Au₆Ge₄₀ both have glasslike thermal conductivity. The samples exhibit thermoelectric figures of merit of about 0.06 at 400 K.