Synthesis and Characterization of Dinuclear Europium Complexes Showing Pure Red Electroluminescence

Abstract

Two dinuclear EuIII complexes have been synthesized by employing β-diketones and 2,2Ј-bipyrimidine (bpm) as sensitizing ligands for the Eu ion and a bridging ligand, respectively, and characterized by various means including single-crystal X-ray crystallography. The use of dibenzoylmethane (dbm) and trifluorothenoylacetone (tta) as β-diketones gave [Eu 2 (dbm) 6 (bpm)] (1) and [Eu 2 (tta) 6 (bpm)] (2). Both show strong intermolecular π-π interactions that may be responsible for their high melting points. The analysis of the absorption, excitation, and emission spectra of the dinuclear com-

New dinuclear lanthanide(III) complexes based on 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedione and 2,2′-bipyrimidine

“…Dinuclear lanthanide complexes provide an opportunity to study a rare class of compounds to detect f-f interactions [12]. 2,2 0 -Bipyrimidine (bpm) is a potentially bridging ligand, however there is a limited number of structurally characterized lanthanide complexes employing bpm as bridging ligand and most of them were reported during this study or during the preparation of this report [8][9][10][11].The goal of our work is to determine whether the coordinatively unsaturated Ln(fod) 3 chelates would coordinate on both sides of the bis-diimine ligand with large as well as small lanthanide metal ions to form a single dimetallic molecular species and to see the effect of such coordination on the properties of the metal ions. Therefore, this report describes the synthesis of a series of dinuclear lanthanide (Nd, Eu, Tb and Lu) complexes using 2,2 0 -bipyrimidine as bridging ligand and 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionate as terminal ligands.…”

“…The lanthanide based materials find many applications such as in light-emitting devices [2], sensors [3], and liquid crystalline materials [4] and as luminescent probes [5]. Strategies for the design of stable trivalent lanthanide complexes relies on the use of chelating ligands [1] such as polyaminopolycarboxylates, cryptands, calixarenes, podands, helicates and among others the complexes with b-diketones [6] are most popular and intensively studied lanthanide complexes.Majority of lanthanide b-diketonate complexes studied are monometallic [6] and the reports on dinuclear lanthanide diketonate complexes is still scanty [7][8][9][10][11]. Dinuclear lanthanide complexes provide an opportunity to study a rare class of compounds to detect f-f interactions [12].…”

Full-color OLEDs based on conjugated materials

“…Recently, more attention has been paid to OLEDs providing single-color emission (three primary colors: blue, green and red) and white emission [3,9,12,32,33,41,[72][73][74][75][76][77][78][79][80][81][82][83][84][85][86][87][88][89][90][91]. Our group has dedicated our efforts to the investigation of OLEDs based on conjugated materials, and tricolor, yellow as well as white emission were obtained from the devices.…”

Monometallic europium, terbium, and neodymium complexes formed from the bridging ligand 2,3-bis(2-pyridyl)pyrazine: Crystal structure and temperature dependent luminescent properties

“…Over the past decade these bridging ligands have been utilized to form homodinuclear and heterodinuclear lanthanide complexes [1][2][3][4][5][6][7][8][9][10][11][12]. Of the numerous polyazine bridging ligands available two have received particular attention in forming lanthanide bridged complexes; 2,2 0 -bipyrimidine (bpm, I) and to a lesser extent 2,3-bis(2-pyridyl)pyrazine (dpp, II).…”

“…Molecular structure of Eu(tdh)3 dpp showing atomic numbering scheme, 50% thermal ellipsoid probability, H-atoms omitted for clarity. The C7 position is hidden behind F3.…”