The following quarterly report covers the period during February 16 to May 15, 1963. This report is divided into sections covering the separate activities during this period, studying the thermal behavior of the F-center in RbCl.

From abstract: "Resistivities of solid solution alloys in the systems Gd-Lu, Tb-Lu, Gd-Er, and Y-Lu were measured from 4.2-320°K to determine the behavior of the resistivity in alloy systems with magnetic phenomena arising from localized magnetic moments. A large contribution to the residual resistivity is caused by the random distribution of these localized moments through the lattice. An analysis of the lattice resistivity of the metals shows large variations across the heavy rare-earth series which are possibly correlated with the change of c/a ratio of the metals and the attendent changes in the Fermi surface geometry."