Magnetic properties of praseodymium ions in Na2O–Pr2O3–SiO2 glasses
نویسندگان
چکیده
Sodium praseodymium silicate glasses of nominal composition 0.3Na2O xPr2O3 (0.7 x)SiO2, where 0pxp0:10; have been studied by magnetisation and X-ray photoelectron spectroscopy (XPS). The magnetisation data fail to collapse to a single curve in the M versus H=T representation for all values of x and the spread increases with x; indicating an increase in the magnetic exchange interaction. The M versus H data acquired at different temperatures have been fitted with a Brillouin function by refining the number of Pr ions in each glass sample. It was found that most of the Pr ions are in Pr valence state and only a small fraction (p5%) in the Pr state. Analysis of the XPS line shape indicates only the presence of Pr ions in these glasses. r 2002 Elsevier Science B.V. All rights reserved.
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