Energy Transfer Studies in Tb-Yb Co-Doped Phosphate Glasses.

Detailed optical properties of Tb-Yb co-doped phosphate glasses were performed based on their emission spectra and decay measurements. Under blue excitation of Tb at 488 nm, the intensity of Yb emissions gradually enhanced upon increasing the Yb content until 1 mol% indicated an energy transfer from Tb to Yb. Otherwise, under near infrared excitation of Yb at 980 nm, these glasses exhibit intense green luminescence, which led to cooperative sensitization of the D level of Tb ions.

Magnetism in Mixed Valence, Defect, Cubic Perovskites: BaIn Fe O, = 0.25, 0.50, and 0.75. Local and Average Structures.

The series BaIn Fe O, = 0.25, 0.50, and 0.

5-(1-1,2,3-Triazol-5-yl)isophthalic Acid: A Versatile Ligand for the Synthesis of New Supramolecular Metallogels.

The gelation ability of 5-(1-1,2,3-triazol-5-yl)isophthalic acid () in the presence of different metal acetates has been studied in different solvents and ligand/metal ratios. This manuscript is focused on the metallogel obtained from the combination of and copper(II) acetate, which has been used as a model system in terms of characterization and gelation studies. Sonication treatment of the initial mixture of compounds and the nature of the counter anion were found to be critical factors for the supramolecular assembly of the metal/ complexes and, hence, for the formation of stable and homogeneous metallogels.

High pressure luminescence of Nd in YAlO perovskite nanocrystals: A crystal-field analysis.

Pressure-induced energy blue- and red-shifts of the F → I near-infrared emission lines of Nd ions in YAlO perovskite nano-particles have been measured from ambient conditions up to 29 GPa. Different positive and negative linear pressure coefficients have been calibrated for the emission lines and related to pressure-induced changes in the interactions between those Nd ions and their twelve oxygen ligands at the yttrium site. Potentiality of the simple overlap model, combined with ab initio structural calculations, in the description of the effects of these interactions on the energy levels and luminescence properties of the optically active Nd ion is emphasized.

Yttrium orthoaluminate nanoperovskite doped with Tm ions as upconversion optical temperature sensor in the near-infrared region.

The thermal sensing capability of the Tm-doped yttrium orthoaluminate nanoperovskite in the infrared range, synthetized by a sol-gel method, was studied. The temperature dependence of the infrared upconverted emission bands located at around 705 nm (F→H) and 800 nm (H→H) of YAP: Tm nanoperovskite under excitation at 1210 nm was analyzed from RT up to 425 K. Calibration of the optical sensor has been made using the fluorescence intensity ratio technique, showing a high sensitivity in the near-infrared compared to other trivalent rare-earth based optical sensors working in the same range.