Yasuchika Hasegawa 교수

A chameleon luminophore: A temperature-sensing material is reported that has a high thermostability (see picture). The material is composed of color-changing luminescent coordination polymers containing EuIII and TbIII ions. The coordination polymer exhibits a high emission quantum yield Φ of 40 % at room temperature and a temperature-sensing ability over a wide range of 200–500 K.

Radiation rates and emission quantum yields of Eu(III) were modified using asymmetric deuterated Eu(III) complexes doped in poly(methyl methacrylate) (PMMA) deuterated tris-(hexafluoroacetylacetonato)europium(III) with phospine oxide in order to produce lowthreshold levels for laser transmission and amplifier emissions. Geometric structures of asymmetric Eu(III) complexes were determined by single-crystal X-ray diffraction and Judd−Ofelt analysis. Luminescent polymers were fabricated by incorpor

The 4f–4f emission of Tb(III), Eu(III), and Sm(III) complexes plays an important role in the design of monochromatic green, red, and deep-red luminescent materials for displays, lighting, and sensing devices. The 4f–4f emission of Yb(III), Nd(III), and Er(III) complexes is observed in the near-infrared (IR) region for bioimaging and security applications. However, their absorption coefficients are extremely small (ε < 10 L mol−1 cm−1). In this review, photosensitized luminescent lanthanide(III)

Luminescent lanthanide coordination polymers composed of lanthanide ions and organic joint ligands exhibit characteristic photophysical and thermostable properties that are different from typical organic dyes, luminescent metal complexes, and semiconductor nanoparticles.

Historical and recent advances of lanthanide mononuclear complexes, polynuclear clusters, coordination polymers (CPs) and metal–organic frameworks (MOFs) with temperature-dependent luminescence are reviewed for future thermo-sensitive paints.

Luminescence of Nd(III) in an organic solvent having C-H bonds was achieved for the first time by complexing Nd(III) with long-chain perfluoroalkylated ligands such as bis(perfluorooctylsulfonyl)aminate (pos). The complex [Nd(pos)(3)] gave an emission quantum yield of 3.0+/-0.5 % in undeuterated acetone. The bulky pos ligands suppress the excitation of C-H vibrations, energy migration at diffusional collision, and the coordination of acetone molecules (see picture) to the Nd(III) center, which o

The deuterated tris(hexafluoroacetylacetonato)neodymium(III) complex, Nd(HFA-D)3, was obtained by keto−enol tautomerism reaction of Nd(HFA)3 in methanol-d4. The emission of Nd(HFA-D)3 was observed in the following anhydrous deuterated organic solvents: methanol-d4, acetone-d6, THF-d8, DMF-d7, and DMSO-d6. The intensity and lifetime of the emission in DMSO-d6 are much superior to those in other deuterated solvents. The specific interaction of DMSO molecules with Nd(HFA)3 was confirmed by 13C NMR

The distorted coordination structures and luminescence properties of novel lanthanide complexes with oxo-linked bidentate phosphane oxide ligands--4,5-bis(diphenylphosphoryl)-9,9-dimethylxanthene (xantpo), 4,5-bis(di-tert-butylphosphoryl)-9,9-dimethylxanthene (tBu-xantpo), and bis[(2-diphenylphosphoryl)phenyl] ether (dpepo)--and low-vibrational frequency hexafluoroacetylacetonato (hfa) ligands are reported. The lanthanide complexes exhibit characteristic square antiprism and trigonal dodecahedro

The effect of solvent molecule on the emission properties of Sm(hfa)3(phen)2 (hfa = hexafluoroacetylacetonato, phen = phenanthoroline) was investigated using acetone, acetonitrile, and pyridine. 5G(5/2) --> 5H(9/2) transition intensities in pyridine were found to be larger than those in corresponding acetone and acetonitrile. The radiative rate constant in pyridine (4.8 x 10(2) s(-1)) was 2 times larger than those in acetonitrile (2.6 x 10(2) s(-1)) and acetone (2.3 x 10(2) s(-1)), although the

The enhanced magneto-optical properties of nanoscaled lanthanide chalogenide semiconductors which have a wide energy gap were observed at around 500 nm for the first time. The nanoscaled semiconductors, Eu(1-x)Se nanoparticles 1 (cubic shapes) and 2 (spherical shapes), were synthesized by the thermal reduction of Eu(III) ion with organic ligands containing Se atoms. The resulting Eu(1-x)Se nanoparticles were characterized by X-ray diffraction, high-resolution transmission electron microscopy, en