Study of magnetic properties of Mn1−xCuxCr2S4 by: High-temperature series expansions

Abstract The high-temperature series expansions method applied in the systems Mn 1− x Cu x Cr 2 S 4 in the range 0⩽ x ⩽1. The exchange interactions and the magnetic exchange energies are calculated by using the probability law. The high-temperature series expansions have been applied in the spinel Mn 1− x Cu x Cr 2 S 4 systems, combined with the Pade approximants method, to determine the magnetic phase diagram, i.e. T C versus dilution x . The critical exponent associated with the magnetic susceptibility ( γ ) is deduced. The obtained value of γ is insensitive to the dilution ratio x and may be compared with other theoretical results based on 3D Heisenberg model.