We report direct spectroscopic evidence for atom migration during the initial stage of electron irradiation in spinel MgAl2O4. Time-dependent electron energy-loss spectroscopy of the Mg and Al L-23 edges shows that both Mg and Al have a tendency to occupy the octahedral interstices under electron irradiation, along with a slight expansion of the Al-O bonding distance, but there is little change in the structural framework of oxygen. The process is irreversible at room temperature. (C) 2010 Elsevier B.V. All rights reserved.
机构:
Int Adv Res Ctr Powder Met & New Mat ARCI, Ctr Adv Ceram, Hyderabad 500005, Andhra Pradesh, IndiaInt Adv Res Ctr Powder Met & New Mat ARCI, Ctr Adv Ceram, Hyderabad 500005, Andhra Pradesh, India
机构:
Int Adv Res Ctr Powder Met & New Mat ARCI, Ctr Adv Ceram, Hyderabad 500005, Andhra Pradesh, IndiaInt Adv Res Ctr Powder Met & New Mat ARCI, Ctr Adv Ceram, Hyderabad 500005, Andhra Pradesh, India