A comprehensive research on new DyCo2Mnx (x=0.0-1.0) Laves phases

DyCo2Mnx (x = 0.0, 0.2, 0.4, 0.6, and 1.0) compounds were synthesised and found to all be single-phase, isostructural to DyCo2 (MgCu2 Laves phase cubic structure (Fd-3 m) at room temperature). DyCo2Mn ex-hibits a huge coercivity field HC = 21,170 Oe at 5 K. The magnetic transition at Curie temperature TC, was observed as first order for DyCo2 but second order for the Mn doped compounds. Using Kouvel-Fisher plot, critical isotherm analysis and Arrott-Noaks plot techniques, a detailed critical exponents analysis was carried out on these transitions: critical exponents beta approximate to 0.5, gamma approximate to 1.0, and delta approximate to 3.0 were derived indicating that all the second-order transitions belong exhibit long-range magnetic interactions during the magnetic transi-tions. High-resolution synchrotron X-ray measurements confirm that there are crystal structure transfor-mations sychronised with the magnetic transitions from paramagnetism to ferrimagnetism (PM-FM) at TC in the x = 0.0 and 0.2 cases with crystal structure changing from cubic (Fd-3 m) to tetragonal (I41/amd), However structures remain cubic (Fd-3 m) for x = 0.4, 0.6, and 1.0.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

DyCo2Mnx compounds with different Mn dopant concentrations were synthesized and their structures and magnetic properties were studied. The Mn doping induces a second-order magnetic transition and long-range magnetic interactions during the transition. High-resolution X-ray measurements confirm the structural changes during the magnetic transition.