# Formation enthalpies of Al-Mn-Pd and the structure of the $i$-AlMnPd quasicrystal

## TL;DR

This study uses first-principles calculations to determine formation enthalpies of phases in the Al-Mn-Pd system, including quasicrystal approximants, highlighting the need for experimental validation and further structural refinement.

## Contribution

The paper provides the first-principles calculated formation enthalpies for Al-Mn-Pd phases, including quasicrystal approximants, and emphasizes the importance of experimental reexamination.

## Key findings

- Icosahedral and decagonal quasicrystal approximants are predicted to be stable or nearly stable.
- Results suggest the need for experimental reexamination of phase stability.
- Further refinement of crystallographic and ab-initio structures is recommended.

## Abstract

This paper reports formation enthalpies of phases in the Al-Mn-Pd ternary alloy system as calculated from first principles using electronic density functional theory. We consider all crystal structures as reported in the assessed phase diagrams of the ternary and its binary alloy subsystems (Al-Mn, Al-Pd, and Mn-Pd), as well as additional reported or hypothetical structures. Icosahedral and decagonal quasicrystalline approximants are among the structures that we predict to be stable, or nearly so. Our results suggest the need for careful experimental reexamination of phase stability in each of the alloy systems, in tandem with further efforts to refine crystallographic and ab-initio structures.