Phosphine oxides as luminescent components for modulated emission

Abstract

This TFG presents the synthesis, the structural characterization, magnetic properties and/or luminescence of 4 compounds: rac-BINAPO2 (1), [Tb(acac)3((R)-BINAPO2)] (2a), [Gd(acac)3((R)-BINAPO2)] (3a) and [Eu(acac)3((R)-BINAPO2)] (4a).These lanthanide complexes were synthesized by reaction of Tb(III), Gd(III) and Eu(III) salts with racemic and enantiopure BINAPO2 (1), which is a chiral ligand. The structural characterization reveals that the terbium compound (2a) is mononuclear with the formula [Tb(acac)3((R)-1)], with 1 acting as a bidentate ligand by the phosphoryl groups. The complex is octacoordinated to 8 oxygen atoms and the coordination geometry can be described either as a square antiprism (SAPR-8) or a bicapped trigonal prism (BTPR-8). The magnetic static measurements reveal that 2a exhibit a high intrinsic single ion anisotropy and it does not present SIMs behaviour. Compound 3a follows a Curie law and has an intrinsic single ion isotropic behaviour and show SIMs (Single Ion Magnet) behaviour. The SIMs behaviour can be deduced by the response AC which can be observed on the magnetic dynamic measurements. And the relaxation mechanism process of magnetization has been obtained which follows a Raman and Direct process. The luminescent measurements were performed for compound 2a and 4a indicated that both complexes have an efficient sensitization effect. This fact it is due to the (R)-1 ligand because is a chromophore. Finally, the chiroptical properties have been studied for Gd(III) complexes 3a and 3b, containing the R and S enantiomers of 1 respectively. As expected, the two spectra are mirror images, which confirms the analogous structure of 3a and 3b.