Zinc 2-((2-(benzoimidazol-2-yl)quinolin-8-ylimino)methyl)phenolates : synthesis, characterization and photoluminescence behavior

A series of 2-(2-(1H-benzoimidazol-2-yl)quinolin-8-yliminomethyl)phenol derivatives and their zinc complexes (C1 – C5) were synthesized and fully characterized. The molecular structure of the representative complex C2 was determined by single crystal X-ray diffraction, which revealed that the zinc was five-coordinated with the tetra-dentate ligand and a methanol bound to the metal afford a distorted square-pyramidal geometry. The UV-Vis absorption and fluorescence spectra of the organic compounds and their zinc complexes were measured and investigated in various solvents such as methanol, THF, dichloromethane, and toluene; significant influences by solvents were observed on their luminescent properties; red-shifts for the zinc complexes were clearly observed in comparisons to the free organic compounds

Phase Diagram of Magnetization Reversal Processes in Nanorings

We investigate magnetization reversal processes of magnetic nanorings. Using a recently developed efficient cartesian coordinates fast multipole method, magnetization switching phase diagrams are constructed for such structures. We find that the dominant switching mechanisms strongly depend on the relative spatial dimensions of the rings, i.e. height, width and radius. Furthermore, they are found to depend on a characteristic exchange length scale, which is determined by the competing short-range ferromagnetic and long-range dipolar interactions in these systems. Detailed simulations allow us to identify three novel switching mechanisms, which should be useful for building high density storage systems.Comment: 6 pages, 6 figure