Reporter:Hellmut Eckert
Affiliation:Institut für Physikalische Chemie, WWU Münster, Germany

Time:　  At 1:30PM, Dec. 12, 2011
Place:　　Honored Guest Meeting Room

Welcome to join us!

Abstract:

Glasses and vitroceramics based have been introduced as excellent alternatives to single crystalline host materials for luminescent rare-earth ions with special laser applications. To optimize the luminescent properties of these materials, detailed structural information regarding the local environment of the rare-earth species is essential. This characterization must include the distribution of the rare earth ions over the different crystalline and amorphous components present. While solid state nuclear magnetic resonance (NMR) is in general a promising tool for such purposes, unfortunately, the rare-earth ions themselves cannot be studied by NMR due to their paramagnetism. To overcome this difficulty, we have developed a comprehensive examination strategy consisting of (a) the use of diamagnetic mimics such as 45Sc and 89Y NMR [1], (b) the quantification of paramagnetic broadening effects imparted by the rare-earth ions upon the solid state NMR spectra of framework atoms [2], and (c) the direct study of electron-nuclear interactions as probed by electron spin echo envelope modulation (ESEEM) spectroscopy [3]. Results will be presented for a range of rare-earth containing aluminoborate and –phosphate glasses and ceramics, and extensions to other laser ceramic systems will be discussed.

[1] H. Deters, H.; A. S. S. de Camargo, C. N. Santos, C. R. Ferrari, A. C. Hernandes, A. Ibanez, M. T. Rinke, H. Eckert, J. Phys. Chem. C 113, 16216 (2009).

[2] H. Deters, A. S. S. de Camargo, C. N. Santos, H. Eckert, J. Phys. Chem. C 114, 14618 (2010).

[3] H. Deters, J. F. de Lima, C. J. Magon, A. S. S. de Camargo, H. Eckert, Phys. Chem. Chem. Phys. 2011, in press.