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Raman spectra of (ND4)(2)TeBr6 were recorded in the temperature range 5-300 K, A continuous minimum of the Raman shift and a continuous maximum of the linewidth of the A(1g) mode of the TeBr62- octahedron were observed at T-c = 68 K. Also, the T-2g mode of the TeBr62- octahedron continuously split into two lines below T-c. X-ray diffraction measurements at 10 K indicate that the low-temperature phase has a primitive tetragonal structure, and an antiferro-rotation of the TeBr62- octahedra is associated with the transition. This behaviour indicates a displacive phase transition at T-c.