The Paramagnetism of Color Centers in KCl

Two methods for studying susceptibility changes occurring during thermal and optical alterations in color centers in KCl are described. The magnetic changes accompanying formation of $R^{\prime }$-centers from $F$-centers, and upon completely destroying both $F$- and $R^{\prime }$-centers, indicate that the moment of a $F$-center is that calculated for an $s$-electron, that $R^{\prime }$-centers have a variable moment depending on the distribution of centers, but generally very nearly that of $F$-centers, and that irradiation during $R^{\prime }$-center formation results in a destruction of paramagnetism.