Crystal and electronic structures of metallic Ba ₂Pd ₅Ge ₄

Crystals of a new intermetallic germanide Ba ₂Pd ₅Ge ₄ have been grown out of a binary PdGe flux. Single crystal X-ray diffraction reveals that the compound crystallizes in a novel structure type in the Cmca space group, with a = 10.9296(9) Å, b = 14.1639(12) Å, and c = 5.8808(5) Å at 173(2) K. This structure type features a three-dimensional [Pd ₅Ge ₄] network made of distorted tetrahedral and square planar PdGe ₄ units, with Ba atoms filling the voids. The magnetic susceptibility and the electrical resistivity measurements show that Ba ₂Pd ₅Ge ₄ is a Pauli paramagnet and a metal with the room temperature resistivity value of ρ(300 K) ≈ 0.096 mΩ cm. The band structure calculations confirm that Ba ₂Pd ₅Ge ₄ is a good metal with no magnetic instability.