ELECTRICAL RESISTIVITIES OF SOLUTIONS OF ALKALINE-EARTH METALS IN LIQUID LITHIUM - MEASUREMENT AND INTERPRETATION

Electrical resistivity-composition isotherms (475 less-than-or-equal-t o T/K less-than-or-equal-to 750) are presented for dilute solutions (x (M) less-than-or-equal-to 10 at%) of calcium, strontium and barium in liquid lithium; they increase with increasing composition, but with de creasing gradient. The 625 K resistivity coefficients (DELTArho/OMEGA m; the resistivity increase caused by 1 at% solute) increase from calc ium (0.3) through strontium (0.7) to barium (4.9); however, inclusion of literature data for lithium-magnesium solutions (1.6) shows that th ey exhibit a minimum as a function of solute atomic number. This obser vation is interpreted using the empirical expression DELTArho = G Z/V( solute) + H\V(solute) - V(solvent)\ + J, which relates the resistivity coefficient to the effect a solute atom of different ion core potenti al (Z/V(solute) and different size (\V(solute) - V(solvent)\) has on t he periodic potential of the solvent matrix. The expression also holds for solutions of alkaline earth metals in liquid sodium and for dilut e liquid alkali metal mixtures.