Linear thermal expansivity (1–300 K), specific heat (1–108 K), and electrical resistivity of the icosahedral quasicrystali−Al61.4Cu25.4

Linear thermal expansivity (α, 1-300 K), heat capacity (C p , I -108 K), and electrical resistivity (ρ, 1-300 K) measurements are reported for single grain i-Al 6 1 . 4 Cu 2 5 . 4 Fe 1 3 . 2 quasicrystals as a function of sample processing. While ρ(T) is sensitive to sample treatment, both C p and a are relatively insensitive (to a few percent) except at the lowest temperatures (below 4 K), where an inverse correlation between p and the electronic C p coefficient γ appears to exist. Dispersion effects (deviations from Debye-like behavior) in both C p and the lattice Gruneisen parameter Γ are large and comparable with those for single grain i-Al 7 1 Pd 2 1 Mn 0 8 quasicrystal and its Al 7 2 Pd 2 5 Mn 0 3 approximant [Phys. Rev. B 65, 184206 (2002)]. Since the 0-K Debye temperature [θ 0 =536(2) K] is in reasonable agreement with that from 4-K elastic constants [548(8) K], a previous postulate for AlPdMn that these large dispersion effects are associated with high dispersion lattice modes in off-symmetry directions also appears to apply to i-Al-Cu-Fe. A comparison with other C p data suggests that the major effects of sample treatment (and composition) are reflected, with a few exceptions, in the values of γ, with remarkably similar lattice contributions.