Surface energy of liquid metals at the melting temperature related to bulk liquid structure

The product σχ_Tm of surface energy σ and isothermal compressibility σχ_Tm for liquid metals at the melting temperature T_m yields a length l ranging from about 0.2 to 0.5 Å over the entire range of liquid metals. The variation of l, which has been related brfore to the thickness of the liquid-vapour interface, is shown to be accurately represented by , where the constant c is determined empirically, K_B and N being the Boltzmann factor and Avogadro's number respectively, and S_Tm(0) the bulk liquid structure factor in the long wavelength limit at the melting temperature. A microscopic interpretation of l is proposed.