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Abstract: Four Zn-Ln salen complexes are formed with the Schiff base ligand bis(3-methoxysalicylidene)ethylene-1,2-phenylenediamine (H2L). The complexes are trinuclear [LnZn2L2(OAc)2]·CF3SO3·Et2O (Ln = Eu (1) and Tb (2)), and dinuclear [EuZnL(OAc)(NO3)2MeOH] (3) and [TbZnL(OAc)2(NO3)] (4). The structures of 1–4 were determined by single crystal X-ray crystallographic studies and the respective luminescence properties in MeCN solution were determined. [Copyright &y& Elsevier]

Abstract: Cyclometalated iridium(III) complexes have been synthesized for use in a variety of photophysical applications, including polymer light emitting diodes (PLEDs). A series of new complexes with one electrochemically polymerizable ligand and two phenylpyridine(ppy)-based ligands have been prepared: [Ir(ppy)2L][PF6](1), [Ir(F-mppy)2L][PF6](2), and [Ir(Br-mppy)2L][PF6](3), where L=3,8-bis(2,2′-bithien-5-yl)-1,10-phenanthroline. The ancillary ppy ligands can be easily varied synthetically to tune emission color of the monomer from blue–green to red. The solid state structure of complex 1 has been obtained by single crystal X-ray crystallography. Conducting polymer materials have been prepared by electropolymerization of monomers and were characterized through XPS analysis and spectroscopic studies. [Copyright &y& Elsevier]

Abstract: Five heterobimetallic Cu–Ln complexes of general formula [CuLn(HL)2(NO3)3(MeCN)2]·2Et 2O (Ln=Eu 1, Tb 2, Er 3, Yb 4 and Nd 5) were prepared with a new multidentate benzimidazole ligand based on 4-bromo-2-[2-(5-bromo-2-hydroxy-3-methoxy-phenyl)-benzoimidazol-1-ylmethyl]-6-methoxy-phenol (H 2 L 1 ) or its bis-methoxy substituted analog (H 2 L 3 ). In the solid state the structures of 1–4 exhibit supramolecular 3D-networks which are formed by the linking of C–H⋯O and C–H⋯π interactions. Compound 5 does not exhibit an extended supramolecular network. [Copyright &y& Elsevier]

Abstract: Visible and near infrared (NIR) luminescence are observed in heterobimetallic 3d–4f Schiff base complexes [ZnLEu(OAc)(NO3)2]·EtOH·H2O (2) and [ZnLNd(OAc)(NO3)2(H2O)]·EtOH (3), respectively (H2L= N,N′-bis(5-bromo-3-methoxysalicylidene)phenylene-1,2-diamine, OAc=acetate). [Copyright &y& Elsevier]

A 7-metal Cd(II)-Nd(III) nanocluster was constructed using a salen-type Schiff base ligand, and it shows NIR luminescence response to nitrofuran antibiotics with high sensitivity and selectivity. [Display omitted] A 7-metal Cd(II)-Nd(III) nanocluster 1 (molecular size 0.7×1.5×2.5 nm) was synthesized from a new salen-type Schiff base ligand. 1 exhibits NIR luminescence response to nitrofuran antibiotics (NFAs) with high sensitivity and selectivity, which is not affected by other antibiotics. The quenching constants (K sv) and limits of detection (LOD) of NFAs range from 3.24×104 M−1 to 0.94×104 M−1 and from 4.2×10−7 M to 7.9×10−6 M, respectively. It also can be used to detect NFAs in real antimicrobial drugs sold in pharmacy. [ABSTRACT FROM AUTHOR]

Three multinuclear Cd–Ln complexes [Er 2 Cd 2 L 2 (OAc) 2 (OH) 2 (OCH 3 ) 2 ] ( 1 ) and [Ln 2 CdL 2 (NO 3 ) 4 ] (Ln = Er ( 2 ) and Sm ( 3 )) were prepared using a flexible long-chain Schiff base ligand. Interestingly, 1 – 3 show nano-rectangular-like structures (i.e. 8 × 12 × 12 Å for 1 and 7 × 10 × 15 Å for 2 and 3 ). 1 has a tetranuclear structure with two lanthanide ions and two Cd 2+ enclosed by two flexible Schiff base ligands (H 2 L), while 2 and 3 show trinuclear structures with the Cd(II) ion located in the center. Upon excitation of the ligand-centered absorption bands, 1 – 2 and 3 show typical emission spectra for Er 3+ and Sm 3+ ions, respectively. Luminescence studies exhibit that 1 shows higher emission quantum yield than 2 . [ABSTRACT FROM AUTHOR]

Abstract: Herein we report for the first time the complete characterization and photophysical properties of tris(dibenzoylmethanido)(1,10-phenanthroline)samarium(III) (Sm(DBM)3phen) in the absence of a polymer matrix. The solid state structure of Sm(DBM)3phen has been determined by single-crystal X-ray crystallography and shows the geometry of the local coordination environment around the samarium(III) ion to be a slightly distorted square antiprism. The absolute quantum yield and luminescence lifetime were measured as 0.86±0.40% and 41±2μs, respectively. [Copyright &y& Elsevier]

Two tetranuclear Ni–Ln complexes [Ni 2 Ln 2 (L) 2 (OAc) 6 ] (Ln = Eu (1) and Yb (2)) were prepared using a new Schiff base ligand with Ph–S–Ph backbone and their visible and NIR emission properties were investigated. Two tetranuclear Ni–Ln nanoclusters [Ni 2 Ln 2 (L) 2 (OAc) 6 ] (Ln = Eu (1) and Yb (2)) were synthesized by the using of a new Schiff base ligand with Ph-S-Ph backbone. The sulfur atom of the Schiff base ligand is coordinated with the Ni2+ ion. 1 and 2 have planar structures and their molecular sizes are about 6 × 11 × 19 Å. Upon the excitation of ligand-centered absorption, 2 exhibits the typical NIR luminescence of Yb3+. The lanthanide luminescence lifetime (τ) and quantum yield (Φ em) of 2 in CH 3 CN are 5.18 μs and 0.04%, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Solvent and reaction stoichiometry dictate the products isolated from reactions of the dinuclear precursor complex [ZnNdL(H2O)(NO3)3] (H2L= N,N′-bis(3-methoxy-salicylidene)ethylene-1,2-diamine) with the anionic multidentate linker 1,4-benzenedicarboxylate (1,4-BDC). With a 2:1 molar ratio of ZnNd:Na21,4-BDC in CH3CN–EtOH the tetranuclear complex [Zn2Nd2L2(1,4-BDC)(NO3)4(EtOH)2]·2MeCN (1) is produced while hexanuclear [Zn4Nd2L4(1,4-BDC)2]·(NO3)2 ·2Et2O·4H2O (2) can be isolated from a DMF–EtOH mixture. A 4:1 mole ratio in DMF–EtOH gave the unusual polynuclear complex [Zn4Nd2L4(1,4-BDC)2]·[ZnNdL(NO3)3(OAc)]2 (3). The NIR photophysical properties of the new compounds are reported. [Copyright &y& Elsevier]