Measurements of the Hall coefficient and electrical conductivity are reported for solutions of lithium in liquid ammonia. The concentration range is from 1.2 to 14 mol percnt; metal (MPM) and the temperature range is from near 200 to 240deg;K, except in the miscibility gap. Hall coefficients equal to the values expected from the metalhyphen;valencehyphen;electron density are found above 9 MPM. Below 9 MPM the measured Hall coefficient Rmincreases to about twice the freehyphen;electron valueR0. The latter result does not agree with that previously reported by Kyser and Thompson.Rmis temperature independent at all concentrations. Data for the electrical conductivitysgr;show thermal activation of the mobility below 8 MPM. Changes in the concentration dependence of bothRmandsgr;are observed near 3, 5, and 8 MPM. The solutions behave as liquid metals above 9 MPM. As the concentration is decreased from 9 to 3 MPM, departure from metallic behavior occurs and various criteria for metallic conduction are no longer satisfied. We believe deep traps are present below 9 MPM. At concentrations near 3 MPH the influence of free electrons is no longer seen.
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