Stability of Copper Atoms Embedded in Sodium-Chloride Crystals

Abstract

Because it has been pointed out by Nagasaka et al. that the optical absorption spectrum of copper atoms embedded in alkali-chloride crystals may depend on the position of the copper atoms, we calculate the relation between the optimal position and the total energy of copper atom embedded in NaCl crystal by means of the first-principles pseudopotential plane-wave-expansion method. These results shows that most stable position of embedded Cu⁺ ion in these alkali halide system are not the substitutional on-center site but off-center site along ‹111› axis.