Formation
and stability of ternary phases in the Ho–Ag–Sn and Tm–Ag–Sn metallic systems
Chem.
Met. Alloys 9 (2016) 135-146
https://doi.org/10.30970/cma9.0343
L. ROMAKA,
The isothermal sections of the
phase diagram of the Ho–Ag–Sn ternary system at 673 K and 873 K were constructed in the whole concentration range using
X-ray diffraction and EPM analyses. The interaction between the elements
results in the formation of three ternary compounds at 673 K: HoAgSn (LiGaGe-type, space group P63mc, a = 0.4667(1),
c = 0.7313(2) nm), Ho3Ag4Sn4
(Gd3Cu4Ge4-type, space group Immm, a = 0.4519(2), b = 0.7280(3),
c = 1.5091(3) nm), and HoAgSn2
(Cu3Au-type, space group Pm-3m, a = 0.4525(2) nm).
At 873 K two ternary compounds (HoAgSn,
LiGaGe-type and HoAgSn2, Cu3Au-type) were found. Three
ternary compounds exist in the Tm–Ag–Sn system at 873 K: TmAgSn (ZrNiAl-type, space group P-62m, a = 0.72635(9),
c = 0.4435(1) nm), Tm(Ag,Sn)2
(CaIn2-type, space group P63/mmc,
a = 0.46534(2), c = 0.72649(4) nm) and TmAgSn2 (Cu3Au-type, space
group Pm-3m, a = 0.45033(2) nm).
DSC/DTA analyses showed a limited stability range for Ho3Ag4Sn4
and the existence of a phase transition for the TmAgSn compound. DFT
calculations predict metallic-like behavior for both HoAgSn2 and Ho3Ag4Sn4.
The distribution of the electron localization
function (ELF) in Ho3Ag4Sn4.
Keywords
Intermetallics / Electronic structure / Diffraction /
Differential scanning calorimetry