Low temperature preparation and characterization of In1−xLnxBO3 (x=0.0 and 0.05; Ln=Gd, Eu, Dy and Sm): ESR of In0.95Gd0.05BO3 and emission of In0.95Eu0.05BO3

Indium borate and rare earth substituted indium borates (In(1-x)Ln(x)BO(3) (x=0.0 and 0.05; Ln=Gd, Eu, Dy and Sm)) are prepared at low temperature by metathesis reaction using InCl(3), LnCl(3) and NaBO(2). They are characterized by powder XRD and infrared spectroscopy. All the compositions (In(1-x)Ln(x)BO(3)) crystallize in hexagonal lattice with calcite structure. These borates gave characteristic IR vibrations of planar BO(3) group. Spin-Hamiltonian parameters for Gd(3+) are deduced from room temperature electron spin resonance spectrum of In(0.95)Gd(0.05)BO(3). The electron spin resonance spectrum of In(0.95)Gd(0.05)BO(3) gave several anisotropic lines with g2.0. The ESR spectrum of the sample belongs to the "intermediate" category with 1/4H(CF)/hnu1. The local symmetry of Eu(3+) in In(0.95)Eu(0.05)BO(3) is obtained from its emission spectrum. The R/O ratio of In(0.95)Eu(0.05)BO(3) suggests the occupation of In(3+) site by Eu(3+) with near symmetric octahedral geometry.