Through an analysis of the absorption spectrum of Nd(3+) : Na Beta Alumina and derivation of Judd/Ofelt parameters, a model for the nearest neighbor crystal field of the Nd(3+) ion has been developed. The proposed model indicates that residual sodium in partially exchanged samples is responsible for distorting the symmetric orientation of conduction plane oxygen. This in turn induces a shift in the Nd ion within a sixfold symmetric arrangement of oxygen ions thereby inducing a linear field term in the crystal field parameters. This is responsible for the anomalous absorption strength in ND(3+) : Na Beta double prime Alumina. (ref link)
Lynn Garry Salmon <>{