CRITICAL PHENOMENON ANALYSIS OF SURFACE-TENSION OF LIQUID-METALS

An estimation of the surface tension of metal at far higher temperatures than the melting point has been done on the basis of the following assumptions: (i) The one third law is valid for liquid metal. (ii) The free random walk. of atoms yields the density distribution near the liquid-gas interface. Based on above assumptions the following expressions of surface tension are obtained: (1) The surface tension is given by gamma=A (T-c- T)(B) from the melting point to the critical point, where T-c is the critical temperature and B is the critical exponent. (2) The critical exponent B is theoretically estimated to be 11/9. (3) The coefficient A is given by A=alpha(theta(t)V(t)(-2/3))(nu), where theta(t) and V-t are the reduced temperature and the atomic volume at the triple point, respectively. The matters bearing similarity (the metals in a group and non-polar liquids) have a definite set of (alpha, nu). (4) T-c is expressed as T-c= T+B gamma/s, where s is the surface entropy. T-c should be calculated from gamma and s at the melting point.