The magnetic order of a manganese vanadate system with two-dimensional striped triangular lattice

TL;DR

This study investigates the magnetic properties of a manganese vanadate compound with a two-dimensional striped triangular lattice, revealing antiferromagnetic order and the effects of geometrical frustration.

Contribution

It provides detailed experimental insights into the magnetic structure of Mn$_5$(VO$_4$)$_2$(OH)$_4$, highlighting its layered antiferromagnetic order and lattice topology.

Findings

Long-range antiferromagnetic order below 45 K

Magnetic moments confined within layers and parallel to the b-axis

Reduced magnetic moments due to frustration and low-dimensionality

Abstract

Results of magnetization and neutron diffraction measurements of the manganese vanadate system Mn$_5$(VO$_4$)$_2$(OH)$_4$ are reported. The crystal structure of this compound contains triangular [Mn$_3$O$_{13}$] building blocks that produce two-dimensional Mn$^{2+}$ magnetic networks with striped triangular topologies. The Mn sheets are connected through the nonmagnetic vanadate tetrahedra extending along the $a$-axis. Magnetization measurements performed on single crystals reveal the onset of a long-range antiferromagnetic order below approximately 45 K. The magnetic structure is N\'{e}el-type with nearest-neighbor Mn atoms coupled via three or four antiferromagnetic bonds. The magnetic moments are confined within the layers and are oriented parallel to the $b$ direction. The magnitudes of ordered moments are reduced, presumably by geometrical frustration and the low-dimensionality of the lattice structure.