Reentrant melting and multiple occupancy crystals of bounded potentials: Simple theory and direct observation by molecular dynamics simulations.

Aspects of the phase coexistence behavior of the generalized exponential model (GEM-m) and bounded versions of inverse power potentials based on theory and molecular dynamics (MD) simulation data are reported. The GEM-m potential is ϕ(r)=exp(-r^{m}), where r is the pair separation and m is an adjustable exponent. A simple analytic formula for the fluid-solid envelope of the Gaussian core model which takes account of the known low- and high-density limiting forms is proposed and shown to represent the simulation data well.

Bounded inverse power potentials: Isomorphism and isosbestic points.

The bounded inverse power (BIP) interaction pair potential, ϕ(r)=1/(a+r), where a and the exponent, n, are constants which control the interaction softness, q is a positive integer, and r is the pair separation, is shown to exhibit isomorphic scaling as does the well-known inverse power potential, i.e., where a = 0.