THE ELECTRONIC SPECIFIC HEAT OF LITHIUM–MAGNESIUM ALLOYS

Abstract

The main feature of the results of specific heat measurements on lithium- -magnesium alloys (alloys contain 1 and 10 atomic% magnesium) is the smooth variation of both the electronic specific heat coefficient and the Debye temperature between the values for the pure metals. As an explanation of the similarity of the results, it is assumed that the lithium and alloys are transformed to the hexagonal phase. The variation of the electronic specific heat coefficient on going from pure lithium to pure magnesium is due to the variation in the average number of electrons per atom. The variation may also be attributed to an alteration in the density of states at the Fermi level and to alterations in the effects of the electron-phonon and electron-electron interactions on the electronic specific heat. The observed electronic specific heat decreases with increase in electron density while the Sommerfeld free electron value increases with increase of electron density. The specific heats are 389, 386.7, 366.3, and 292.7 mu cal/ deg K/sup 2/ g-atom, respectively, for lithium, lithium-1 atomic % magnesium, lithium-10 atomic% magnesium, and magnesium. (N.W.R.)