A series of linear sandwich single-ion magnets containing [Er(COT)] fragment were selected to probe the magneto-structural correlations using methods. For prolate shaped Er ion, an equatorially coordinating geometry is preferable to achieve high axial anisotropy. Our calculations confirm that the increasing transversal crystal field (CF) induced by equatorial ligands truly enhances the energy barrier.
View Article and Find Full Text PDFTo explore the influences of magnetic interactions on the relaxation dynamics of single-molecule magnets (SMMs) and to understand the relationship between single-ion relaxation and the relaxation of a molecular entity, it is very important to design dinuclear lanthanide-based SMMs with two-step relaxation processes. Here, three Dy complexes of compositions [Dy(L)(NO)(MeOH)] (1), [Dy(L)(NO)(EtOH)] (2), and [Dy(L)(NO)(DMF)]·0.5EtOH (3) (HL = 2-(((2-hydroxy-3-methoxybenzyl)imino)methyl)-4-methoxyphenol) were successfully synthesized via elaborately introducing different terminal solvent ligands.
View Article and Find Full Text PDFA deep-red emission and lipid droplets-targeted fluorescence probe (named ZFPy) for effective bioimaging of bisulfite was developed from flavone moiety and benzoindole derivative based on intramolecular charge transfer (ICT) and Förster resonance energy transfer (FRET) platform. ZFPy displayed promising fluorescence parameters including bright deep red fluorescence (615 nm), large Stokes shift (205 nm), extended emission window gap (140 nm), high absolute fluorescence quantum yield (4.1%) and stable emission signal output.
View Article and Find Full Text PDFComplete active space self-consistent field (CASSCF) combined with restricted active space spin interaction with spin-orbit coupling (RASSI-SO) was used to probe why single-ion magnets (SIMs) composed of the "prolate" lanthanide ion ErIII cannot possess huge energy barriers. According to the proposal by Long et al., equatorially coordinated ligand environments are preferable for "prolate" lanthanide ions to have large energy barriers.
View Article and Find Full Text PDFTwo five-coordinate mononuclear Co(ii) complexes [Co(12-TMC)X][B(C6H5)4] (L = 1,4,7,10-tetramethyl-1,4,7,10-tetraazacyclododecane (12-TMC), X = Cl- (1), Br- (2)) have been studied by X-ray single crystallography, magnetic measurements, high-frequency and -field EPR (HF-EPR) spectroscopy and theoretical calculations. Both complexes have a distorted square pyramidal geometry with the Co(ii) ion lying above the basal plane constrained by the rigid tetradentate macrocyclic ligand. In contrast to the reported five-coordinate Co(ii) complex [Co(12-TMC)(NCO)][B(C6H5)4] (3) exhibiting easy-axis anisotropy, an easy-plane magnetic anisotropy was found for 1 and 2via the analyses of the direct-current magnetic data and HF-EPR spectroscopy.
View Article and Find Full Text PDFA unique fluorescent probe (ZACA) for the monitoring of SO2 derivatives was developed from coumarin and benzoindoles based on FRET and ICT. ZACA exhibited an active emission signal, large Stokes shift, wide emission window distance, and high photostability. It also possessed many advantages in the ratiometric detection of HSO3-/SO32- including low detection limit and high selectivity and sensitivity.
View Article and Find Full Text PDFWe report on the first, to the best of our knowledge, direct generation of pulsed vortex beams at 2 µm from a ${ Q}$Q-switched Tm:LuYAG laser. High-energy Laguerre-Gaussian (${{\rm LG}_{0,l}}$LG) pulsed laser beams with well-defined handedness are selectively excited through spatially matched pump gain distribution and asymmetric cavity loss without using any intracavity handedness-selective optical elements. Pulse energies of 1.
View Article and Find Full Text PDFWe demonstrate, to the best of our knowledge, the first direct vortex beam generation in the 3 μm spectral region by employing an Er:YO ceramic laser. Controllable handedness with high purity is achieved by introducing asymmetric cavity loss and reducing the number of longitudinal modes. The average orbital angular momentum of the produced scalar vortex beam is quantitatively evaluated to be 0.
View Article and Find Full Text PDFDerivatization of carbohydrates with aminooxy agents to form oximes can be used for qualitative and quantitative analysis of carbohydrates; however, the formation of isomeric products limits its application. A new reductive oxyamination procedure developed for the analysis of monosaccharides with a novel fluorescent O-substituted aminooxy reagent, 4-((aminooxy)methyl)-6-chloro-7-hydroxycoumarin (AOCC), is reported. In this procedure, monosaccharides undergo an oxime formation reaction with AOCC and are then readily reduced with 2-picoline-borane, followed by analysis with high-performance liquid chromatography with fluorescence detection.
View Article and Find Full Text PDFVortex beams carrying orbital angular momentum (OAM) have been recently investigated intensely in optical communication systems, as using OAM mode multiplexing simultaneously with other conventional multiplexing techniques is the key to further expand data capacity. This article demonstrates a wavelength- and OAM-tunable vortex laser at 1.6 µm in an Er:YAG system.
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