| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1616150 | Journal of Alloys and Compounds | 2012 | 5 Pages |
Samples of the xGd2O3(1 − x)[GeO·PbO] and xNd2O3(1 − x)[GeO·PbO] vitreous systems with 0 ≤ x ≤ 0.15 were prepared and investigated by X-ray diffraction, FTIR spectroscopy and magnetic susceptibility measurements (in addition, the samples containing gadolinium ions were investigated by electron paramagnetic resonance (EPR) spectroscopy). FTIR spectroscopy investigation shows that the studied samples consist of both GeO4 and GeO6 structural units, the GeO4 being predominant. The increase of the gadolinium or neodymium ion content of the samples determines the GeO4 → GeO6 conversion process. FTIR data suggest that the rare earth ions present in the vitreous matrix play a network modifier role. Magnetic susceptibility data show that the magnetic behavior of the studied samples is due to the presence of the Gd3+ and Nd3+ ions. These ions appear as isolated species for low rare earth oxide contents, x ≤ 0.03–0.05, while for higher contents appear as magnetically coupled species, too.EPR spectroscopy data obtained for the xGd2O3(1 − x)[GeO2·PbO] samples show that, in addition to the network modifier role of the rare earth ions suggested by the FTIR data, the Gd3+ ions play also the network former role.
► Lead–germanate glasses with rare earth ions (gadolinium/neodymium) were characterized. ► XRD investigation revealed the amorphous nature of all the studied samples. ► The GeO4, GeO6 and PbO4 structural units were evidenced by FTIR spectrocopy. ►The magnetic RE ions from vitreous matrices are coupled via RE–O–RE superexchange interactions. ► The EPR data suggest that the gadolinium ions play not only the glass modifier role proved by the IR data, but also the glass former role.
