Analysis of the Refractive Indices of TiO2, TiOF2, and TiF4: Concept of Optical Channel as a Guide To Understand and Design Optical Materials
文摘
In an effort to gain insight into how optical properties of insulating materials are affected by a change in chemicalcomposition, we investigated the dielectric functions of titanium dioxide, TiO2, and its fluorine-substituted phases,TiOF2 and TiF4, by electron energy loss spectroscopy measurements and density functional theory electronic bandstructure calculations. The refractive indices of these compounds are found to be inversely proportional to their cellvolumes per formula unit. This observation was explained by employing the concept of optical channels. Our studyindicates that the light-scattering properties of insulating compounds can be controlled by modifying their cell volumes.