Field-induced single-molecule magnet behavior in a Dy-based coordination polymer

School of Basic Sciences, Indian Institute of Technology Mandi - Mandi-175005 (H.P.), India

Received: 26 March 2020
Accepted: 1 June 2020

Abstract

A new mononuclear dysprosium-based coordination polymer {Dy-CP}is investigated for the magnetic properties. DC susceptibility of the Dy-CP does not exhibit any long-range ordering down to 1.8 K and the negative value of the Curie constant () indicate the dominance of antiferromagnetic interactions between the Dy (III) spins. AC susceptibility of the Dy-CP exhibits absence of single molecular magnet (SMM) behavior at zero field and shows signal of quantum tunneling magnetization (QTM) below 8 K. However, on the superimposition of a DC field (3 kOe), a frequency-dependent relaxation peak emerged at and the QTM signal is suppressed at higher fields. The intermediate value of reflects the formation of superparamagnetic state. The magnetic susceptibility analysis (Arrhenius fit) yields characteristics pre-relaxation factor and energy barrier , indicating the slow spin relaxation. The Cole-Cole fit shows further evidence for the single ion spin relaxation. Thus, the magnetic measurements support the SMM behavior in the Dy-CP under the application of DC magnetic field.