On the thermodynamic properties of the generalized Gaussian core model

Abstract

We present results of a systematic investigation of the properties of the generalized Gaussian core model of index n. The potential of this system interpolates via the index n between the potential of the Gaussian core model and the penetrable sphere system, thereby varying the steepness of the repulsion. We have used both conventional and self-consistent liquid state theories to calculate the structural and thermodynamic properties of the system; reference data are provided by computer simulations. The results indicate that the concept of self-consistency becomes indispensable to guarantee excellent agreement with simulation data; in particular, structural consistency (in our approach taken into account via the zero separation theorem) is obviously a very important requirement. Simulation results for the dimensionless equation of state, βP/o, indicate that for an index-value of 4 a clustering transition, possibly into a structurally ordered phase might set in as the system is compressed. © B.M.Mladek, M.J.Fernaud, G.Kahl, M.Neumann.