Structural response to the magnetic pre ordering in LiFeSi2O6

TL;DR

This study explores how the structure of LiFeSi2O6 changes with temperature, revealing a three-dimensional magnetic behavior and providing insights into its potential multiferroic properties.

Contribution

It presents the first detailed analysis of the temperature-dependent structural and magnetic phase transitions in LiFeSi2O6, highlighting its unique three-dimensional magnetic interactions.

Findings

Structural transition at ~220K

Magnetic transition at ~18K

Three distinct temperature regions with different lattice behaviors

Abstract

We investigate the temperature evolution of the structural parameters of potential ferrotoroidic LiFeSi2O6 compound across structural and magnetic phase transitions. The structural transition (TS)is around 220K and the paramagnetic to antiferromagnetic transition (TN) is around 18K. The lattice parameters exhibit unusual temperature dependence and based on its behaviour, the exper- imental results can be divided into 3 regions.In region I (300K to 240K), the cell parameters are mainly governed by mere thermal effect. As the compound enters region II (below 240K to 50K), the lattice parameters show non linear behaviour. In this region, the exchange pathways that lead to the magnetic interactions within and between the Fe-Fe chains do not show significant response.The region III (below 50K) is dominated by the magnetic contribution where we observe setting up of intra and inter-chain magnetic interaction. This behaviour is unlike other low dimensional com- pounds like Ca3Co2O6, Sr3NiRhO6, MnTiO3 etc. thereby suggesting the magnetism in LiFeSi2O6 is of three dimensional nature. The present results will be helpful in understanding the evolution of the spin rings that give rise to net toroidal moment and hence its multiferroic behaviour.