Role of Tin and Carbon in the magnetic interactions in Mn$_3$SnC

TL;DR

This study investigates how tin and carbon influence magnetic interactions in Mn$_3$SnC, revealing that their deficiencies alter structural strain and magnetic order, leading to complex magnetic ground states.

Contribution

It provides new insights into the role of Sn and C deficiencies in tuning magnetic interactions and structural strain in Mn$_3$SnC.

Findings

C deficiency increases tensile strain and enhances ferromagnetism.

Sn deficiency reduces strain, affecting both ferromagnetic and antiferromagnetic interactions.

Structural strain from Sn and C deficiencies causes complex magnetic ground states.

Abstract

In this paper we attempt to understand the role of tin and carbon in magnetic interactions in Mn$_3$SnC. Mn$_3$SnC exhibits a time dependent magnetic configuration and a complex magnetic ground state with both ferromagnetic and antiferromagnetic orders. Such a magnetic state is attributed to presence of distorted Mn$_6$C octahedra with long and short Mn--Mn bonds. Our studies show that C deficiency increases the tensile strain on the Mn$_6$C octahedra which elongates Mn--Mn bonds and strengthens ferromagnetic interactions while Sn deficiency tends to ease out the strain resulting in shorter as well as longer Mn--Mn bond distances in comparison with stoichiometric Mn$_3$SnC. Such a variation strengthens both, ferromagnetic and antiferromagnetic interactions. Thus the structural strain caused by both Sn and C is responsible for complex magnetic ground state of Mn$_3$SnC.