Cluster glass behaviour in MnMn<inf>0.25</inf>Sb

Magnetic properties of intermetallic MnMn0.25Sb crystallizing in the NiAs-type hexagonal structure are reported. A spin-glass transition at Tf ≈ 10.7 K was identified from Ac susceptibility measurements. The value of the Mydosh parameter (φ≈0.06). was further indicative of cluster spin glass like state. The frequency dependence of Tf was investigated by critical slowing-down model and Vogel-Fulcher law. The characteristic time constant of τ0∗≈0.18×10−7s was analysed using power-law for a single spin-flip and a critical exponent of zv=4.37±0.14. The characteristic time constant was obtained from the Vogel-Fulcher law for a single spin-flip τ0≈7.96×10−8s, and T0=6.49±0.21K. The cluster spin-glass behaviour in the current system is due to the existence of both competing interactions and atomic disorder at 2d site.