Optically active homogeneous mixtures of cholesteric liquid crystals and anew coordination compound: Eu(Thenoyltrifluoroacetonate)(3). (Cholesteryl tetradecanoate or nonanoate)

The reactions of cholesteryl pelargonate (P) or myristate (M) with Eu(theno yltrifluoroacetonate)(3).3H(2)O (EuTTA(3)) at room temperature give the cor responding complexes Eu(wwthenoyltrifluoroacetonate)(3). (Cholesteryl pelar gonate), n H2O (1) and Eu(thenoyltrifluoroacetonate)(3). (Cholesteryl myris tate), n H2O (2) respectively. When adding these two fluorescent complexes to liquid crystal compounds, optically active and aggregate free mixtures a re obtained, containing up to 2.5 molar percent of dopant without loosing t he mesogenic properties. The different phases exhibited by these mixtures h ave been identified. The luminescence properties of these Eu3+ complexes in cholesteric phases have been investigated.