Study on the observation of Eu2+ and Eu3+ valence states in low silica calcium aluminosilicate glasses.

نویسندگان

  • J A Sampaio
  • M C Filadelpho
  • A A Andrade
  • J H Rohling
  • A N Medina
  • A C Bento
  • L M da Silva
  • F C G Gandra
  • L A O Nunes
  • M L Baesso
چکیده

The optical, magnetic and structural properties of Eu doped low silica calcium aluminosilicate glasses were investigated. The optical absorption coefficient presented two bands at 39,246 and 29,416 cm(-1), which were assigned respectively to the [Formula in text], and [Formula in text] transitions of Eu(2+). The fluorescence measured at 300 K on a sample doped with 0.5 wt% of Eu(2)O(3) exhibited a broad band centered at 17,350 cm(-1), which is attributed to the [Formula in text] transition of Eu(2+), whereas the additional peaks are due to the [Formula in text] transitions of Eu(3+). From magnetization and XANES data it was possible to evaluate the fractions of Eu(2+) and Eu(3+) for the sample doped with 0.5 and 5.0 wt% of Eu(2)O(3), the values of which were approximately 30 and 70%, respectively.

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عنوان ژورنال:
  • Journal of physics. Condensed matter : an Institute of Physics journal

دوره 22 5  شماره 

صفحات  -

تاریخ انتشار 2010