Document Type

Article

Publication Date

November 2017

Publication Title

Physical Review Materials

Volume

1

Issue Number

6

DOI

10.1103/PhysRevMaterials.1.064001

Disciplines

Materials Science and Engineering

Abstract

The crystallographic and magnetic properties of the cleavable 4d3 transition metal compound α−MoCl3 are reported, with a focus on the behavior above room temperature. Crystals were grown by chemical vapor transport and characterized using temperature dependent x-ray diffraction, Raman spectroscopy, and magnetization measurements. A structural phase transition occurs near 585 K, at which the Mo-Mo dimers present at room temperature are broken. A nearly regular honeycomb net of Mo is observed above the transition, and an optical phonon associated with the dimerization instability is identified in the Raman data and in first-principles calculations. The crystals are diamagnetic at room temperature in the dimerized state, and the magnetic susceptibility increases sharply at the structural transition. Moderately strong paramagnetism in the high-temperature structure indicates the presence of local moments on Mo. This is consistent with results of spin-polarized density functional theory calculations using the low- and high-temperature structures. Above the magnetostructural phase transition the magnetic susceptibility continues to increase gradually up to the maximum measurement temperature of 780 K, with a temperature dependence that suggests two-dimensional antiferromagnetic correlations.

Comments

SJSU users: Use the following link to login and access the article via SJSU databases.This article was published in Physical Review Materials volume 1, issue 6, 2017 and can also be found online here.Copyright © 2017, American Physical Society

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