Partial atomic volume and partial molar enthalpy of formation of the 3d metals in the palladium-based solid solutions

Abstract

The composition dependence of the average atomic volume, as well as of the enthalpy of formation, was investigated for the palladium-containing binary systems with the 3d metals. The partial atomic volume and the partial molar enthalpy of formation of the 3d metals were determined for the palladiumbased solid solutions (Pearson symbol cF4, space group Fm3 -m, Cu type). The 3d early transition metals (scandium, titanium, and vanadium) as well as the 3d 10 4s 2 . . . 3d 10 4s 2 4p metals (zinc and gallium) show (1) the partial atomic volume for the palladium-based solid solutions smaller than is their atomic volume in the nonbonded state and (2) significantly large (negative) values of the partial molar enthalpy of formation indicating a strong bond energy between atoms of palladium and those of the 3d early transition metals (as well as a strong bond energy between atoms of palladium and zinc or gallium atoms). The 3d late transition metals (and chromium) show (1) the partial atomic volume for the palladium-based solid solutions larger than is their atomic volume in the nonbonded state and (2) low (negative) values of the partial molar enthalpy of formation indicating weak bond energy between atoms of palladium and those of the 3d late transition metals.

Machine-learned interatomic potentials for alloys and alloy phase diagrams

“…As is clear from Fig. 5, the melting behavior of our MTP potential qualitatively matches the experimental line [58][59][60][61][62] . However, although the entire line has roughly the same shape, it is shifted from the experimental results by ~200 K. The liquidus-solidus gaps are also in reasonable agreement with experimental data when the same shift of 200 K is included (added in Fig.…”

Machine-learned Interatomic Potentials for Alloys and Alloy Phase Diagrams

“…As is clear from Figure 5, the melting behavior of our MTP potential qualitatively matches the experimental line [97,99,128,137,148]. However, although the entire line has roughly the same shape, it is shifted from the experimental results by ∼200 K.…”

Crystal chemical investigation of the solid solutions of antimony and bismuth in palladium and platinum

“…In contrast, for the 3d late transition metals (chromium· · ·nickel) solved in palladium, the partial atomic volumes are larger than the atomic volumes of these metals [15]. The values of the partial molar enthalpy of formation are slight negative, indicating weak bond energy between palladium-atoms and those of the 3d late transition metals [15].…”

“…Large volume changes and very negative values of the partial molar enthalpy of formation (indicating strong bond energy) were observed also for the early transition metals (A 3 , A 4 = scandium, yttrium· · ·zirconium and hafnium) solved in palladium [13,14]. In contrast, for the 3d late transition metals (chromium· · ·nickel) solved in palladium, the partial atomic volumes are larger than the atomic volumes of these metals [15]. The values of the partial molar enthalpy of formation are slight negative, indicating weak bond energy between palladium-atoms and those of the 3d late transition metals [15].…”

“…From these data, the average atomic volume of the solid solutions and the partial atomic volume of the B 11-14 elements in the A 10 solvents (showing the Cu structure, Pearson symbol cF4) were determined. The solid solubility of the light B 15 elements -phosphorus and arsenic -in the A 10 metals is negligible [4]. For antimony, the maximum solid solubility in nickel amounts to x Sb < 0.09 (at 1370 K) [4].…”