The growing interest in controlled nuclear energy has been accompanied by a requirement for increased knowledge of the behavior of materials under high energy density conditions. The efficiency of fission reactors can be improved with coolant fluids capable of maintaining large molecular densities at high temperatures and moderate pressures. The high melting points of most of metals place the liquid state at temperatures too high for easy experimental investigation. A relatively complete mapping of the liquid region to include location of the liquid-vapor coexistence curve through the critical point is available only for Na, K, Rb, Cs, and Hg, and for these not all measurements are in agreement. For most metals the critical region lies at higher pressures and temperatures than are accessible to conventional experimental techniques. To provide needed engineering data and to stimulate theoretical understanding of low density liquid metals, an investigation of the equilibrium properties of metals above 2000 K and 0.1 GPa is the objective of this work.
