Large Diamagnetism of AV2Al20 (A = Y and La)

TL;DR

This study reports unexpectedly large diamagnetic responses in AV2Al20 compounds with A = Y and La, suggesting a unique electronic structure evolution related to lattice expansion.

Contribution

It reveals significant diamagnetism in Y and La AV2Al20 compounds, contrasting with other similar compounds, indicating a novel electronic property linked to lattice parameters.

Findings

Y and La compounds show large diamagnetic susceptibilities.

Diamagnetic response increases with lattice constant.

Response is comparable to bismuth per unit volume.

Abstract

We find anomalously large diamagnetic responses in the cage compounds AV2Al20 where A = Y and La, not A = Al0.3, Sc0.4, and Lu, despite the apparent similarities in crystal and electronic structures among these compounds. The magnetic susceptibilities of the Y and La compounds become -1.94 and -7.44 x 10-4 cm3 mol-1 at 10 K, respectively, the latter of which corresponds to approximately one-quarter of that of bismuth, a well-known diamagnetic material, in terms of unit volume. The origin is not clear but may be related to a specific evolution in the band structure, as the diamagnetic response increases with increasing lattice constant.