Magnetic Transformations in the Organic Conductor kappa-(BETS)2Mn[N(CN)2]3 at the Metal-Insulator Transition

TL;DR

This study investigates magnetic properties of the organic conductor kappa-(BETS)2Mn[N(CN)2]3 around its metal-insulator transition at 25K, revealing complex magnetic transitions involving manganese and pi-electron spins.

Contribution

It provides new insights into the magnetic behavior and field-induced transitions in this organic conductor near the metal-insulator transition.

Findings

Manganese subsystem transitions from paramagnetic to frozen state at T_MI

Detection of a field-induced spin-flop-like transition below T_MI

Evidence of coupling between pi-electron spins and manganese 3d spins

Abstract

A complex study of magnetic properties including dc magnetization, 1H NMR and magnetic torque measurements has been performed for the organic conductor kappa-(BETS)2Mn[N(CN)2]3 which undergoes a metal-insulator transition at T_MI~25K. NMR and the magnetization data indicate a transition in the manganese subsystem from paramagnetic to a frozen state at T_MI, which is, however, not a simple Neel type order. Further, a magnetic field induced transition resembling a spin flop has been detected in the torque measurements at temperatures below T_MI. This transition is most likely related to the spins of pi-electrons localized on the organic molecules BETS and coupled with the manganese 3d spins via exchange interaction.