Solid-State Syntheses of Rare-Earth–Doped Sr1-xLn2x/3MgP2O7 (Ln = Gd, Eu, Dy, Sm, Pr, and Nd; x = 0.05) by Metathesis Reactions and their Spectroscopic Characterization

Abstract

ABSTRACT Rare-earth–doped strontium magnesium diphosphates of composition Sr1-xLn2x/3MgP2O7 (Ln = Gd, Eu, Dy, Sm, Pr, and Nd; x = 0.05) were prepared by metathesis reaction. These diphosphates were characterized by powder X-ray diffraction (XRD), energy dispersive spectra (EDS), and infrared spectroscopy. All these compounds were found to crystallize in monoclinic lattice with P21/n space group. The compositions of all the samples were confirmed from their EDS spectra. The infrared spectra of all the samples were characterized by bands due to units. The 31P MAS-NMR of these compounds suggests the presence of two types of phosphorous ions in the lattice. The electron-spin resonance spectrum of Sr1-xGd2x/3MgP2O7 (x = 0.05) gave “U”-type spectrum due to the low symmetry of the Gd3+ ion in the host lattice. The local symmetry of Eu3+, Dy3+, and Sm3+ in Sr1-xLn2x/3MgP2O7 (Ln = Eu, Dy, and Sm; x = 0.05) was obtained from their room-temperature luminescence spectra.