Eu3+-doped gadolinium oxyhydroxide Gd1-xEuxOOH crystals were synthesized by the flux method. The X-ray diffraction data for the crystals were well refined assuming a monoclinic structure with the P21/m space group. Gd...Eu3+-doped gadolinium oxyhydroxide Gd1-xEuxOOH crystals were synthesized by the flux method. The X-ray diffraction data for the crystals were well refined assuming a monoclinic structure with the P21/m space group. Gd1-xEuxOOH (x ≤ 0.2) crystals showed strong red emission, and the highest fluorescence quantum yield (Φf) was 0.27, obtained for x = 0.10. Φf decreased rapidly as the Eu3+ content x increased above 0.2, owing to concentration quenching. Analysis with a percolation model indicated three-dimensional energy transfer between the Eu3+ ions.展开更多
A new method for the crystal growth of alkaline-earth palladate CaPd3O4 was developed. The crystals were synthesized on a voltage-applied electrode in a molten chloride solvent. The maximum length of the crystal was a...A new method for the crystal growth of alkaline-earth palladate CaPd3O4 was developed. The crystals were synthesized on a voltage-applied electrode in a molten chloride solvent. The maximum length of the crystal was about 1.5 mm. The X-ray diffraction data were refined well by assuming a cubic structure of the space group Pm n, and the lattice constant a was 5.7471 (10) ?. The temperature dependence of the resistivity showed semiconductor-like characteristics with a very small activation energy Ea of 0.45 meV at low temperatures, and the resistivity at 300 K was 0.1 cm. The temperature dependence of the molar magnetic susceptibility showed the Curie-Weiss paramagnetic behavior with a small molar Curie constant Cmol of 5.0(1) × 10-3 emu K/(mol Oe), indicating the existence of localized spin moments.展开更多
文摘Eu3+-doped gadolinium oxyhydroxide Gd1-xEuxOOH crystals were synthesized by the flux method. The X-ray diffraction data for the crystals were well refined assuming a monoclinic structure with the P21/m space group. Gd1-xEuxOOH (x ≤ 0.2) crystals showed strong red emission, and the highest fluorescence quantum yield (Φf) was 0.27, obtained for x = 0.10. Φf decreased rapidly as the Eu3+ content x increased above 0.2, owing to concentration quenching. Analysis with a percolation model indicated three-dimensional energy transfer between the Eu3+ ions.
文摘A new method for the crystal growth of alkaline-earth palladate CaPd3O4 was developed. The crystals were synthesized on a voltage-applied electrode in a molten chloride solvent. The maximum length of the crystal was about 1.5 mm. The X-ray diffraction data were refined well by assuming a cubic structure of the space group Pm n, and the lattice constant a was 5.7471 (10) ?. The temperature dependence of the resistivity showed semiconductor-like characteristics with a very small activation energy Ea of 0.45 meV at low temperatures, and the resistivity at 300 K was 0.1 cm. The temperature dependence of the molar magnetic susceptibility showed the Curie-Weiss paramagnetic behavior with a small molar Curie constant Cmol of 5.0(1) × 10-3 emu K/(mol Oe), indicating the existence of localized spin moments.