Hellmut Eckert

UNIVERSITY OF SAO PAULO

E-mail : eckertifsc [dot] usp [dot] br

2011 - present  Professor Titular, São Carlos Institute of Physics, University of São Paulo.
2001-2009    Founder and Director, NRW International Graduate School of Chemistry, WWU Münster.
2010 -  2016     Editor in Chief, Solid State Nuclear Magnetic Resonance, Elsevier.
1998 -  2011  Editor, Chemistry of Materials, American Chemical Society.
1995 - 2022  Professor (C4), Institute of Physical Chemistry, WWU Münster.
1987 - 1996  Assistant, Associate, and Full Professor, Department of Chemistry, University of California, Santa Barbara.
1984 - 1987  Associate Scientist, California Institute of Technology.
1982 - 1984  Postdoctoral fellow, Rutgers University, New Brunswick, USA.
1982  Dr. rer. nat., WWU Münster

The group works on several fundamental research projects in the areas of oxide, fluoride, and chalcogenide glasses and glass-ceramics for high-technology applications as photonic materials, solid-state battery components, and as bioactive and catalytic materials. Using the full inventory of advanced solid-state nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) methodologies, we explore structure-function correlations in these materials, and are trying to understand the structure/dynamics aspects of the glass-to-crystal transition in glass-ceramics. In this context we are also developing innovative methodological aspects of modern solid-state NMR spectroscopic techniques. Current topics in this research field include the development of new approaches using dipolar and quadrupolar NMR of “unusual” low-gamma nuclei.

FAPESP, CEPID program, “Center of Research, Technology and Education in Vitreous Materials” (CERTEV), project 2013/07793-6, Principal Investigator and Vice-coordinator, 2019-2024
DFG 413550885, New optical materials based on rare-earth doped oxyfluoride glasses and glass ceramics: structural studies by magnetic resonance methods. 2018-2023.
Nippon Electric Glass: Structure-Property Correlations in Crack-Resistant Glasses. 2020-2023.
CNPq Research Productivity fellowship 2011-2025.

The development of new rare earth-doped crystals, glasses and ceramics of high optical quality as laser materials is a particularly active branch of current materials research. Designing materials with optimized emission properties requires detailed knowledge of the structural features at the atomic level. This includes the local bonding situation of the rare earth ion and its second coordination sphere, the extent of clustering of these ions and their distribution to the different micro and nano phases in the resulting composite materials.

The project aims to gain a basic understanding of the spectroscopic and photophysical properties of such materials, whose structure is to be elucidated with the help of NMR and EPR methods. Fluoroaluminate, fluoride phosphate and fluoride tellurite glasses are the focus of the investigations. To achieve these goals, a comprehensive solid-state NMR and EPR strategy must be developed and used to characterize the local environment of the emitter ions. The structural information obtained in this way and its correlation with the optical properties of the materials examined should then help to develop new design strategies for high-performance laser materials.

Spectroscopic results on some fluorophosphotellurite optical fiber glasses, illustrating the effect of F incorporation: decrease of mid-range IR absorption and distinction of different phosphorus sites by 31P NMR. Model of the network structure illustrating different Te (red and orange) and P (blue and purple) environments.

Structural rearrangements during sub-Tg relaxation and nucleation in lithium disilicate glass revealed by a solid-state NMR/MD strategy, H. Bradtmüller, A. Gaddam, H. Eckert, E. D. Zanotto, Acta Materialia 2022, 240, 118318.

Solid-State NMR Investigation of Fast Sodium Ion-Conducting Glass Ceramics: The System Na3+3x-yRE1-xPySi3-yO9 (RE = Sc, Y), I. d’Anciães Almeida Silva, A.C.M. Rodrigues, H. Eckert, J. Am. Ceram. Soc. 2022, 105, 7502-7521.

Correlating Sulfur Solubility with Short-to-Intermediate Range Ordering in the Structure of Borosilicate Glasses, R. Saini, S. Kapoor, D. R. Neuville, R. E. Youngman, B. M. Cerrutti, J. S. McCloy, H. Eckert, A. Goel, J. Phys. Chem. C 2022, 126, 655-674.

Structure-Property Relations in Crack Resistant Alkaline Earth Aluminoborosilicate Glasses Studied by Solid State NMR, M. Logrado, H. Eckert, T. Murata, S. Nakane, H. Yamazaki, J. Am. Ceram. Soc. 2021, 104, 2250-2267

Composition-Structure-Solubility Relationships in Borosilicate Glasses: Toward a Rational Design of Bioactive Glasses with Controlled Dissolution Behavior, N. Stone-Weiss, H. Bradtmüller, H. Eckert, A. Goel, ACS Appl. Mater. Interf. 2021, 13, 31495-31513.

Combined Experimental and Computational Approach toward the Structural Design of Borosilicate-Based Bioactive Glasses N. Stone-Weiss, H. Bradtmüller, M. Fortino, M. Bertani, R. E. Youngman, A. Pedone, H. Eckert, A. Goel, J. Phys. Chem. C 2020, 124, 17655-17674.

Effect of Boron Incorporation on the Bioactivity and Structure in Mesoporous Bioactive Glasses, L. Deilmann, O. Winter, B. Cerrutti, H. Bradtmüller, C. Herzig, A. Limbeck, O. Lahayne, C. Hellmich, H. Eckert, D. Eder, J. Mater. Chem. B, 2020, 8, 1456-1465.

Structural Characterization of Boron-containing Glassy and Semicrystalline Biosilicate by Multinuclear NMR, H. Bradtmüller, B. M. Cerrutti, M. T. Souza, E. D. Zanotto, H. Eckert, J. Non Cryst. Solids 2019, 505, 390-399.