Optical Properties of the Eu(Thenoyltrifluoroacetonate)3. (Cholesteryl Tetradecanoate or Nonanoate) Complexes

Abstract

We report the optical properties study of two new europium coordination complexes Eu(Thenoyltrifluoroacetonate)₃. (Cholesteryl Pelargonate), n H₂O (EuTTA₃P), Eu(Thenoyltrifluoroacetonate)₃. (Cholesteryl Myristate), n H₂O (EuTTA₃M) and of an optically active cholesteric liquid crystal (CLC) mixture obtained doped with these two fluorescent complexes. Refractive indices of these coordination compounds and of the doped cholesteric liquid crystal mixture have been determined. Wavelength-dependent scattering of these doped cholesteric mixtures has been investigated. Optical absorption and luminescence bands of EuTTA₃P and EuTTA₃M have been measured and assigned to transitions between the energy levels of Eu³⁺. From these optical measurements and using Judd-Ofelt theory, intensity parameters Ω₂, Ω₄ and emission cross-section have been estimated.