Molecular-dynamics study of liquid rubidium

Molecular dynamics has been used to investigate the properties of supercooled liquid states for a model of liquid rubidium. The energy-temperature relation for the reduced density $n^{*}=0.95\mathrm{}$ for liquid, amorphous solid, and bcc crystal phases is presented along with the pair-correlation function, the self-diffusion coefficient, and the transverse-current correlation as functions of temperature for the liquid. The self-diffusion coefficient is found to vary with temperature in a way which correlates with the temperature evolution of the pair-correlation function. The power spectra of the transverse-current correlation function are used to determine the minimum length required for the decay of fluctuations to be describable by linearized hydrodynamics. This length grows rapidly as the amount of supercooling increases and becomes significantly larger than the dimensions of the cube to which periodic boundary conditions are applied.