THE ORDERING TEMPERATURE IN FINE PARTICLE-SYSTEMS

In this paper the origin of the ordering temperature in systems of fine particles in a solid matrix is examined. From theoretical and experimental results, the variation of the reciprocal of the initial susceptibility (chi(i)-1) with temperature is found to be curved when a wide range of temperatures is examined. However if the variation of chi(i)-1 vs. T is examined over a limited range of temperatures an apparent ordering temperature (T0) is predicted from a linear extrapolation of the data. Consequently, in interpreting experimental ordering temperature other contributions in addition to particle interactions must be considered.