Layered CrGe1-xSe3+y with Cr Kagome Lattice and Antiferromagnetic Ordering

TL;DR

This paper introduces a new layered material, CrGe1-xSe3+y, with a Kagome lattice structure that exhibits antiferromagnetic order below 50 K, expanding the understanding of magnetic behaviors in layered chromium selenides.

Contribution

The study synthesizes and characterizes a novel layered CrGe1-xSe3+y compound with a Kagome lattice and antiferromagnetic properties, contrasting with ferromagnetic behaviors in related materials.

Findings

CrGe1-xSe3+y has a double Kagome layer of Cr atoms.

The compound exhibits antiferromagnetic order below 50 K.

Chromium shows an effective magnetic moment of ~3.9 μB/Cr.

Abstract

We report the synthesis and properties of a new layered material, CrGe1-xSe3+y. The crystal structure was determined by using single crystal x-ray diffraction and transmission electron microscopy. CrGe1-xSe3+y crystallizes with a space group R-3m, featuring a double Kagome layer of chromium atoms, sandwiched between disordered Ge-Se layers. This compound displays antiferromagnetic order below 50 K, unlike the ferromagnetic behavior in CrGeTe3. Chromium displays an effective moment of ~3.9 {\mu}B/Cr, consistent with Cr3+ oxidation. The presence of this phase limits the possibility of a ferromagnetic CrGeSe3 analogous to CrGeTe3.