(321bb) Equation of State for Lennard-Jones Fluid and Chains in the Npt Ensemble

A simple equation of state (EOS) for Lennard-Jones fluid and chains has been derived in the isothermal-isobaric ensemble resulting in a volume explicit EOS. The accuracy of the equation is tested against simulation data for the fluid and Lennard-Jones chains containing up to 100 Lennard-Jones segments. The equation reproduces the compressibility factor with a reasonable degree of accuracy. The equation has the potential of forming the backbone of an equation of state for real chain molecules and polymers.