title: Analysis of the refractive indices of TiO2, TiOF2, and TiF4: concept of optical channel as a guide to understand and design optical materials.
abstract: In an effort to gain insight into how optical properties of insulating materials are affected by a change in chemical composition, we investigated the dielectric functions of titanium dioxide, TiO(2), and its fluorine-substituted phases, TiOF(2) and TiF(4), by electron energy loss spectroscopy measurements and density functional theory electronic band structure calculations. The refractive indices of these compounds are found to be inversely proportional to their cell volumes per formula unit. This observation was explained by employing the concept of optical channels. Our study indicates that the light-scattering properties of insulating compounds can be controlled by modifying their cell volumes.
authors.affiliation: Institut des Matériaux Jean Rouxel, Nantes, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Rocquefelte
authors.forename: Fabrice
authors.initials: F
authors.lastname: Goubin
authors.forename: Yvan
authors.initials: Y
authors.lastname: Montardi
authors.forename: Nicolas
authors.initials: N
authors.lastname: Viadere
authors.forename: Alain
authors.initials: A
authors.lastname: Demourgues
authors.forename: Alain
authors.initials: A
authors.lastname: Tressaud
authors.forename: Myung-Hwan
authors.initials: MH
authors.lastname: Whangbo
authors.forename: Stéphane
authors.initials: S
authors.lastname: Jobic