No abstract

In the title compound, di-μ-acetato-κ(2)O:O;κ(2)O:O'-bis[(6-chloro-2-{(E)-[(pyridin-2-yl)methylimino]methyl}phenolato-κ(3)N,N',O)zinc(II)], [Zn2(C13H10ClN2O)2(C2H3O2)2]·CHCl3, the Zn(II) cation adopts a five-coordinate geometry and is coordinated by two N atoms and one O atom of a tridentate 6-chloro-2-{(E)-[(pyridin-2-yl)methylimino]methyl}phenolate ligand and two O atoms of two bridging acetate groups, but their coordination geometries differ. One Zn(II) cation adopts a distorted trigonal bipyramidal geometry and the other a square-pyramidal geometry. The two acetate ligands bridge two Zn(II) cations with mono- and bidentate coordination modes. The title compound exhibits a strong emission at 460 nm upon excitation at 325 nm with a quantum yield of 23.1%.

Two novel phosphorescent heteroleptic cationic Ir(III) complexes, Ir(bt) 2 (dmpe) (Ir1) and Ir (bt) 2 (dppe) (Ir2), where bt is 2-phenylbenzothiazole, dmpe is 1,2-bis(dimethylphosphino)ethane, and dppe is 1,2-bis(diphenylphosphino)ethane, were designed and synthesized. Their photophysical and electrochemical properties and the X-ray structure of the Ir1 complex were investigated. The prepared Ir(III) complexes exhibited blue-green emissions at 503-538 nm with vibronic fine structures in dichloromethane solution and PMMA film, implying that the lowest excited states are dominated by ligand-based 3 π-π* transitions. The π-acceptor ability of the diphosphine ancillary ligand leads to blue-shift emission. The room temperature photoluminescent quantum yields (PLQYs) of Ir1 and Ir2 were 52% and 45%, respectively, in dichloromethane solution. These high PLQYs resulted from steric hindrances by the bulky cationic iridium complexes. The crystal structure of Ir1 was determined by X-ray crystallography, which revealed that central iridium adopted a distorted octahedral structure coordinated with two bt ligands (N^C) and one dmpe ligand (P^P) showing cis C-C and trans N-N dispositions. The bent nature of the dmpe ligand resulted in a relatively wide bite angle of 83.83 o of P-Ir-P.

Two novel copper(II) bromide complexes with pyridine containing Schiff base ligands, Cu(pmed)Br 2 and Cu(dpmed)Br 2 where pmed = N'-((pyridin-2-yl)methylene)ethane-1,2-diamine (pmed) and dpmed = N,Ndiethyl-N'-((pyridin-2-yl)methylene)ethane-1,2-diamine (dpmed) were synthesized and characterized using Xray single crystal structure analysis, optical and magnetic susceptibility measurements. Crystal structural analysis of Cu(pmed)Br 2 showed that the copper(II) ion has a distorted square-pyramidal geometry with the trigonality index of τ = 0.35 and two intermolecular hydrogen bonds, which result in the formation of two dimensional networks in the ab plane. On the other hand, Cu(dpmed)Br 2 displayed a near square-pyramidal geometry with the value of τ = 0.06. In both compounds, the NNN Schiff base and one Br atom occupy the basal plane, whereas the fifth apical position is occupied by the other Br atom at a greater Cu-Br apical distance. The reported complexes show g ⎟⎜ > g ⊥ > 2.0023 with a d x 2 -y 2 ground state and a penta-coordinated square pyramidal geometry. Variable temperature magnetic susceptibility measurements showed that the developed copper(II) complexes follow the Curie-Weiss law, that is there are no magnetic interactions between the copper(II) ions since the Cu--Cu distance is too far for magnetic contact.

In the title complex, [Ir(C14H8F6N)2(C6H5N2O2)]·0.5CHCl3, the IrIII atom adopts a distorted octa­hedral geometry, being coordinated by three N atoms (arranged meridionally), two C atoms and one O atom of three bidentate ligands. The complex mol­ecules pack with no specific inter­molecular inter­actions between them. The SQUEEZE procedure in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148–155] was used to model a disordered chloro­form solvent mol­ecule; the calculated unit-cell data allow for the presence of half of this mol­ecule in the asymmetric unit.