title: Repulsive step potential: a model for a liquid-liquid phase transition.
abstract: In the framework of the perturbation theory for fluids we study the model with the isotropic repulsive step potential which in addition to the hard core has a repulsive soft core of a larger radius. It is shown that this purely repulsive potential is sufficient to explain a liquid-liquid phase transition and liquid anomalies.
authors.affiliation: Institute for High Pressure Physics, Russian Academy of Sciences, 142190 Troitsk, Moscow Region, Russia.
authors.forename: Valentin N
authors.initials: VN
authors.lastname: Ryzhov
authors.forename: Sergei M
authors.initials: SM
authors.lastname: Stishov