Characterization of the ternary uranium–iron aluminide UFe2Al10

The ternary uranium–iron–aluminium compound UFe2Al10 was characterised in the aluminium-rich part of the U–Fe–Al ternary system. Single crystal studies have shown that it crystallises in the orthorhombic system, space group Cmcm, with a=8.9146(3) Å, b=10.1986(3) Å, c=9.0114(3) Å, and is isostructural to YbFe2Al10. Magnetic measurements did not reveal any magnetic ordering down to 5 K. An effective paramagnetic moment of μB=2.62μB/f.u. and a paramagnetic Curie temperature of θ=−107 K were derived from the fit of the temperature dependence of the susceptibility above 80 K, using the modified Curie–Weiss law. 57Fe Mössbauer spectroscopy shows that UFe2Al10, like YFe2Al10, has an unusually high isomer shift for iron in aluminium-containing intermetallics and confirms that no magnetic ordering occurs down to 5 K.