Preparation, characterization and spectroscopic analyses of Dy(III) β-diketonates with bidentate N donor neutral ligands for displays

Abstract

A group of octa-coordinated, anhydrous in nature luminous compounds whose general formula is [Dy(DPD)3L] where ‘DPD’ denotes 1,3-diphenylprop-1,3-dione and ‘L’ corresponds to 2,2ʹ-bipyridine and its derivatives, has been synthesised and fully characterized by CHN, FTIR, NMR and thermal analyses. Dysprosium ion is chelated with ‘O’ atoms of three bidentate β-diketones and ‘N’ atoms of one bidentate neutral ligand. The NMR spectra of synthesised complexes revealed that the protons of β-diketone and –N donor ligands are shifted in opposite direction due to paramagnetic character of Dy(III) ion. Photophysical and electrochemical characteristics of synthesized complexes were studied by absorption, photoluminescence and cyclic voltammetry techniques. The PL spectra of dysprosium ion generate its characteristic yellow emission due to the hyper intense transition i.e.,4F9/2 → 6H13/2 which is sensitive to the bonding environment of trivalent ion. The optical band gap data and branching ratio (4F9/2 → 6H13/2) confirms the effectiveness of synthesized complexes in displays and magnets.