Magnetism of coupled spin tetrahedra in ilinskite-type KCu$_{5}$O$_2$(SeO$_3$)$_2$Cl$_3$

TL;DR

This paper investigates the magnetic properties of ilinskite-type KCu$_{5}$O$_2$(SeO$_3$)$_2$Cl$_3$, revealing quasi-one-dimensional magnetic behavior due to weakly coupled spin ladders influenced by SeO$_3$ groups.

Contribution

It provides the synthesis, thermodynamic data, and a microscopic magnetic model for the compound, highlighting the impact of SeO$_3$ groups on magnetic interactions.

Findings

Short-range magnetic order around 50 K

Absence of long-range order down to 2 K

Weakly coupled spin ladders explain magnetic behavior

Abstract

Synthesis, thermodynamic properties, and microscopic magnetic model of ilinskite-type KCu$_{5}$O$_2$(SeO$_3$)$_2$Cl$_3$ built by corner-sharing Cu$_4$ tetrahedra are reported, and relevant magnetostructural correlations are discussed. Quasi-one-dimensional magnetic behavior with the short-range order around 50\,K and the absence of long-range order down to at least 2\,K is observed experimentally and explained in terms of weakly coupled spin ladders (tubes) with a complex topology formed upon fragmentation of the tetrahedral network. This fragmentation is rooted in the non-trivial effect of the SeO$_3$ groups that render the Cu--O--Cu superexchange strongly ferromagnetic.