✍ Scribed by Li, X. Z.; Sugiyama, K.; Hiraga, K.; Sato, A.; Yamamoto, A.; Sui, H. X.; Kuo, K. H.
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The crystal structure of the orthorhombic ε-Al~4~Cr phase in the Al–Cr system was determined by single crystal X-ray structure analysis: space group Cmcm (No. 63), a = 12.521(1)Å, b = 34.705(2) Å, c = 20.223(1) Å, V = 8787.7(9) Å, Pearson symbol oC__58420.48, Z = 8, M~r~ = 2256, composition Al~56.23~Cr~14.21~, D
~x~ = 3.41 g/cm^3^; F(000) = 8576, λ (Mo__K~α~) = 0.71069 Å, μ = 4.510 mm^−1^, room temperature, R = 0.068 for 2839 reflections, goodness of fit S = 1.084. There are 55 (13Cr + 42 Al) independent atoms in the unit cell, in which 12 Cr atoms and 28 Al atoms have icosahedral coordination. Interatomic distances cover the ranges of 2.570 Å ∼ 2.646 Å, 2.421 Å ∼ 2.978 Å, and 2.480 Å ∼ 2.983 Å, for Cr–Cr, Cr–Al and Al–Al atomic pairs, respectively. The crystalline phase appears obviously as a layered structure perpendicular to the a-axis. A typical aggregation of the icosahedral clusters in the structure of the ε-Al~4~Cr phase has been pointed out.
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## Abstract The results of an investigation of the structures formed in the range of about Al~73~Pd~27~ to Al~76~Pd~14~Fe~10~ by electron diffraction and high-resolution transmission microscopy are reported. The orthorhombic __ε__ ~6~, __ε__ ~16~, __ε__ ~22~ and __ε__ ~28~ phases were observed in s