Crystalline and magnetic structures in REAlxGa2 − x systems

Crystal-field interactions in the pseudo-ternary compound ErAlxGa2-xstudied by inelastic neutron scattering

“…Analysis by x-ray and neutron diffraction revealed single phases for all three samples. In contrast to earlier work [5,15] (i.e. figure 1) no admixture of the intermediate-c/a AlB 2 or the CeCu 2 phases could be observed for the ErAl 0.5 Ga 1.5 sample.…”

“…The values found for ErAl 1.75 Ga 0.25 are close to those of ErAl 2 [1,2]: they match within 7% for B 4 and 20% for B 6 . However they follow an opposite trend to smaller values as the lattice constant a is reduced in contrast to equation (5), where γ m n ∝ a −(n+1) holds. Hence the partial substitution with Ga ions is likely to change the electronic properties of the solid too.…”

“…Polycrystalline samples of ErAl x Ga 2−x (x = 0.5, 1.0, 1.75) were prepared according to the method described previously in [5,15], i.e. by arc-melting the starting elements ( 99.9% purity) under argon atmosphere.…”

“…Upon partial substitution of the Al ions by Ga many of these pseudo-ternary compounds (e.g. R = Ce, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb) realize a hexagonal AlB 2 phase (space group P 6/mmm) and eventually another closely related structure for x 1 [4][5][6][7][8]. The magnetic structure of a few of these 1 To whom correspondence should be addressed.…”

“…The structural and magnetic properties for x = 2, 1.75, 1.0 and 0.5 are listed in table 1. Phase diagram and lattice constants of ErAl x Ga 2−x at room temperature after Martin and Girgis [5]. Markers refer to measured CEF spectra (ErAl 2 by Purwins and Leson [1]).…”