Defect centers in antimony doped NaCl crystals

The existence of both Sb2+ and Sb3+ in NaCl has been established by a series of correlated experiments like optical absorption, EPR, Electrical conductivity and dielectric loss. Sb2+ gives an optical band at 212 nm and in an arbitraryorientation gives an EPR signal whose direction dependence studies indicate three magnetically inequivalent sites. A vacancy occupying a second neighbour site with respect to the impurity ion satisfactorily, explains the observed spectra. The association energy of the impurity ion has been found to be 0·56 eV from ionic conductivity studies. Dielectric loss measurements give two prominent loss peaks which have been assigned to Sb2+ and Sb3+ on the basis of their temperature variation and other correlated experiments. Radiation damage reduces the Sb3+ content while Sb2+ is not affected. © 1973.