title: Relative Study of Luminescent Properties with Judd-Ofelt Characterization in Trivalent Europium Complexes Comprising ethyl-(4-fluorobenzoyl) Acetate.
abstract: Five new europium(III) complexes Eu(p-EFBA)3.(H2O)2(C1), Eu(p-EFBA)3.neo (C2), Eu(p-EFBA)3.batho (C3), Eu(p-EFBA)3.phen (C4), Eu(p-EFBA)3.bipy (C5) have been synthesized by using ethyl-(4-fluorobenzoyl) acetate (p-EFBA) as β-ketoester ligand and neocuproine (neo), bathophenanthroline (batho), 1,10-phenanthroline (phen) and 2,2-bipyridyl (bipy) as ancillary ligands. The synthesized complexes C1-C5 were characterized by elemental analysis, nuclear magnetic resonance spectroscopy (1H-NMR), infrared (IR) spectroscopy, thermogravimetric analysis (TG/DTG), UV-visible and photoluminescence (PL) spectroscopy. The relative study of luminescence spectra of complexes with the previously reported complexes of isomeric ligand (ortho and meta substituted ligand) indicate the higher luminescence properties of complexes as an effect of fluorine position on β-ketoester ligand. The para substituted ligand shows a remarkable effect on quantum efficiencies and Judd-Ofelt intensity parameters (Ω2,Ω4) of the complexes. The higher value of intensity parameter Ω2associated with hypersensitive5D0→7F2transition of europium(III) ion revealing highly polarizable ligand field. The purposed energy transfer mechanism of complexes indicates the efficient energy transfer in complexes.
authors.affiliation: Department of Chemistry, Maharshi Dayanand University, Rohtak, 124001, India.
authors.forename: Rekha
authors.initials: R
authors.lastname: Devi
authors.affiliation: Department of Chemistry, Maharshi Dayanand University, Rohtak, 124001, India.
authors.forename: Sangeeta
authors.initials: S
authors.lastname: Chahar
authors.affiliation: Department of Chemistry, Maharshi Dayanand University, Rohtak, 124001, India.
authors.forename: S P
authors.initials: SP
authors.lastname: Khatkar
authors.affiliation: Department of Chemistry, Maharshi Dayanand University, Rohtak, 124001, India.
authors.forename: V B
authors.initials: VB
authors.lastname: Taxak
authors.affiliation: Department of Chemistry, Maharshi Dayanand University, Rohtak, 124001, India. pritiboora@gmail.com.
authors.forename: Priti
authors.initials: P
authors.lastname: Boora
keywords: Energy transfer; Infrared spectroscopy; Judd-Ofelt intensity parameters; Luminescence; Quantum efficiency