1. |
- Prchal, Jiri, et al.
(författare)
-
Structural discontinuity in the hexagonal RTA1 compounds : Experiments and density-functional theory calculations
- 2008
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 77:13, s. 134106-
-
Tidskriftsartikel (refereegranskat)abstract
- An anomalous behavior of the lattice parameters is reported for RTAl and R(T,T-')Al compounds, with R a rare-earth element and T and T-' transition metals or Cu. In these compounds, which crystallize in the hexagonal ZrNiAl-type of structure, an abrupt transition in the temperature or composition dependence of the lattice constants a and c is observed with the common feature that values of the c/a ratio around 0.565-0.575 are generally not realized. Total-energy calculations based on density-functional theory show the occurrence of two close energy minima, which explains the observed structural instability and the associated transitions.
|
|