Seminar-“New Magnetic Resonance Approaches Towards the Structural Characterization of Luminescent Ceramic Materials” by Hellmut Eckert/5/12/15, Noon-1pm/CREOL 103

“New Magnetic Resonance Approaches Towards the Structural Characterization of Luminescent Ceramic Materials”

Tuesday, May 12, 2015/12:00-1:00pm

CREOL RM 103

                                                                                                                   

Hellmut Eckert

1 Instituto de Física Sao Carlos, Universidade de Sao Paulo, Brazil

2Institut für Physikalische Chemie, WWU Münster, Germany

Celebrating the International Year of Light 2015

Abstract:

Rare-earth doped glasses and vitroceramics 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 in the glassy state is essential. This characterization must include the distribution of the rare earth ions in space and 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 (45Sc and 89Y NMR), (b) the quantification of paramagnetic broadening effects imparted by the rare-earth ions upon the solid state NMR spectra of framework atoms, and (c) the direct study of electron-nuclear interactions as probed by electron spin echo envelope modulation (ESEEM) spectroscopy. Results will be presented for a range of rare-earth containing fluorophosphates, aluminophosphate, and aluminoborate, glasses and ceramics, and extensions to other laser ceramic systems will be discussed.

Biography:

Hellmut Eckert

Professor of Physical Chemistry at the Westfälische

Wilhelms-Universität, Münster, Germany and

Institute of Physics, University of São Paulo, São Carlos.

e-mail eckerth@uni-muenster.de; eckert@ifsc.usp.br

              

1973 - 1978         Studies of Chemistry, WWU Münster

1982      PhD (Dr. rer. nat.), WWU Münster

1982 - 1984         Postdoctoral fellow, Rutgers University, New Brunswick,USA

1984-1987           Staff Scientist, California Institute of Technology, Pasadena, USA

1987-96               Assistant, Associate, and Full Professor, Analyt. Chemistry, UC Santa Barbara, USA

since 1995           Universitätsprofessor  Physical Chemistry, C4, WWU Münster, Germany

since 2011           Professor Titular, Physics, Universidade São Paulo, São Carlos, Brazil.

Editor, Chemistry of Materials (1998-2011), Editor, Solid State Nuclear Magnetic Resonance (since 1991), Member, Scientific Advisory Board, Alexander-von Humboldt Foundation, Germany (since 2010), ~440 publications, ~ 9500 citations, h-Index 44, CNPq: 1A,

For additional information:

Dr. Leonid B. Glebov

407-823-6983