Application of INAA for investigation of magnesium and aluminium oxide materials

作者：Riekstina Daina; Skvortsova Vera; Veveris Olgerts^*

来源：Journal of Radioanalytical and Nuclear Chemistry, 2013, 298(3): 1907-1911.

DOI：10.1007/s10967-013-2775-5

• INAA
• Transition metal impurities
• Magnesium oxide
• Magnesium aluminum spinel
• Optical properties

The paper presents investigations of changes in optical absorption and photo luminescence spectra of magnesium oxide, and natural and synthetic magnesium aluminium spinel related with the content of transition metal ions (Cr, Fe, Mn) and the irradiation with fast neutrons. Six synthetic single magnesium aluminium spinel crystals with different stoichiometry (MgO center dot nAl(2)O(3)), five natural crystals from Ural and Pamir deposits, and seven MgO crystals were studied. Micro impurities (Cr, Fe, and Mn) and macro component (Mg, Al) quantities have been determined using the instrumental neutron activation analysis technique. Concentrations of impurities in different spinels were found in following ranges: for Cr-1 x 10(-4) to 8 x 10(-2) %, for Mn-2 x 10(-5) to 23 %, for Fe-1 x 10(-4) to 1.2 %. Three ranges of luminescence: 380-460, 650-850 and 850-1,050 nm, were established in the most part of the investigated MgO samples. Analysis shows that the intensity of emission in each of these regions is strongly dependent on the concentration of transition metal ions. Great deviation from the stoichiometry of the irradiated MgO center dot 2.8Al(2)O(3) crystal leads to the local structure of alpha-Al2O3 formation around Cr3+ ions. The orange emission is attributed to Mn2+ in octahedral coordination, it can be assumed that the band at 570 nm is belonging to the complex centre "Mn2+-F+ (or F centre)".

• 出版日期2013-12