Atomic and electronic structure of gadolinium oxide

¹ A.V. Rzhanov Institute of Semiconductor Physics of SB RAS, 13 Lavrentieva ave., 630090 Novosibirsk, Russian Federation
² Nikolaev Institute of Inorganic Chemistry SB RAS, 3 Lavrentiev ave., 630090 Novosibirsk, Russian Federation

^a e-mail: timson@isp.nsc.ru

Received: 16 May 2013
Revised: 1 January 2013
Accepted: 13 December 2013
Published online: 27 January 2014

Abstract

Rare earth gadolinium oxide film has been studied by X-ray absorption fine structure (XAFS) at Gd L₃-edge and energy electron loss spectroscopy (EELS) spectroscopies. XAFS data showed that the nearest Gd coordination shells consist of six oxygen atoms at ~2.308(2) Å and six gadolinium atoms at ~3.57(2) Å corresponding to Gd₂O₃ with a space group of Ia-3. EELS analysis of the film revealed excitations at the energies of 14.2, 19.9 eV which are due to electron transition from the valence band to the conductive one; excitations at the energies of 22.2–23.5 eV originated from valence electrons plasmon oscillations (bulk plasmons); and the excitation at 5.5 eV resulted from the electron transition at defects. When the photon energy changed from 1.5 to 5.0 eV the refractive index increased from 1.92 to 2.15.