Theoretical explanation of optical absorption spectra for nickel ion at the interstitial site of zinc borate nanopowder

Abstract

ABSTRACTZinc borates have been used in a variety of applications, including cellulose fibers, textiles, optical materials, and intumescent systems. They have also received many experimental investigations, including metallic ions doping. However, the relevant theoretical studies are absent, especially for the optical spectra and microstructures of zinc borates contained metallic impurities. In this work, as a typical example, the absorption spectra for nickel ions at the interstitial sites in the zinc borate nanopowders are theoretically investigated from the complete energy matrix method based on the two-spin–orbit parameter model and the suggested local defect model for nickel ion in octahedral symmetry. The theoretical results are in good agreement with the experimental values. The local lattice distortion induced by the impurity nickel at the interstitial site of zinc borate nanopowder is also estimated from the calculations. These results are discussed.