L X-Rays RYIED Oscillations and Proton-NMRD of Gd2O3 Nanoparticles

Abstract

Recently, it was shown that relative yields of X-rays induced by ion impact are not constant but depend on beam energy. In the framework of this problem, pellets of Gd2O3 and a Gd chelate, Gd-DOTA, as well as a 5 nm in diameter Gd2O3 nanoparticles dispersion on a polycarbonate Nuclepore filter, were studied. In this work, it is shown that after subtraction of known matrix effects, relative yield variations still present different patterns for Gd2O3 pellet and Gd2O3 nanoparticles. Proton NMRD T1(ω) data for Gd2O3 nanoparticles and Gd-DOTA water solutions published by Bridot et al. and Toth et al., respectively, were reproduced using a model for paramagnetic substances in water solutions and identical electronic relaxation times. The analysis of both techniques results points collective electron behaviour as the explanation for the different observations on X-ray data of Gd2O3 nanoparticles and bulk material.