Quasicrystal approximants with novel compositions and structures

TL;DR

This paper reports the discovery of new quasicrystal approximants in alloy systems with large atomic size contrast, revealing diverse structures and competing ordering patterns, expanding understanding of quasicrystal formation.

Contribution

It introduces novel quasicrystal approximants with unique compositions and structures, including layered Frank--Kasper phases, in previously unreported alloy systems.

Findings

New quasicrystal approximants identified in alloy systems.

Presence of layered Frank--Kasper structures showing competing orderings.

Structural diversity linked to atomic size contrast.

Abstract

We identify several new quasicrystal approximants in alloy systems in which quasicrystals have not been previously reported. Some occur in alloys with large size contrast between the constituent elements, either containing small Boron atoms, or large Ca/Eu atoms, leading to quasicrystal structures quite different from currently known systems where the size contrast is smaller. Another group of the approximants are layered Frank--Kasper structures, demonstrating competition between decagonal and dodecagonal ordering within this family of structures.