Pseudo hard sphere potential

The pseudo hard sphere potential (PHS) is a piecewise continuous variant of the Mie potential, which is "cut-and-shifted" according to the Weeks-Chandler-Andersen recipe. The potential is given by (Eq. 9):

${\mathrm{\Phi }}_{\mathrm{5}\mathrm{0},\mathrm{4}\mathrm{9}}(r)=\{\begin{array}{cc}50{(\frac{50}{49})}^{49}ϵ[{(\frac{\sigma }{r})}^{50}-{(\frac{\sigma }{r})}^{49}]+ϵ& r<\frac{50}{49}\sigma \\ 0& r\ge \frac{50}{49}\sigma \end{array}$

Molecular dynamics simulations of this idealised model, when performed at a reduced temperature of $T^{*}=1.5$ reproduces results for the hard sphere model (for example, the Carnahan-Starling equation of state), which is generally only amenable to Monte Carlo simulations, or advanced techniques such as Event-driven molecular dynamics.

References

Related reading

• Jorge R. Espinosa , Eduardo Sanz , Chantal Valeriani and Carlos Vega "On fluid-solid direct coexistence simulations: The pseudo-hard sphere model", Journal of Chemical Physics 139 144502 (2013)