Session MOE. There are 6 abstracts in this session.

Session: Inorganics, time: 4:00-4:25
Exploring the Hydration of the Inner Earth: Multinuclear NMR Spectroscopy and Ab Initio Random Structure Searching
Sharon Ashbrook1; David McKay1; Robert Moran1; Andrew Berry2
1University of St. Andrews, St. Andrews, United Kingdom; 2Australia National University, Canberra, Australia
It is thought that the inner Earth contains a vast amount of water in the form of hydrogen bound at defect sites within the nominally anhydrous mantle minerals. Although NMR spectroscopy, with its sensitivity to the local structure is ideal for studying the disordered materials that result, interpretation of the complex spectral lineshapes provides a considerable challenge.
Here we show how the ab initio random structure searching (AIRSS) approach can be used to efficiently generate a large number of potential structural models for hydrous wadsleyite (beta-Mg2SiO4). A clustering approach then identifies unique structures, and comparison to experimental 17O, 29Si, and 1H double-quantum NMR spectra then provides a detailed picture of the atomic-scale structure of this important mineral.

Session: Inorganics, time: 4:25-4:50
Structure, Disorder and Function in Metal-Organic Frameworks – an NMR crystallographic approach
Carsten Tschense1; Thomas Wittmann1; Arobendo Mondal2; Guillaume Maurin3; Martin Kaupp2; Juergen Senker1
1University of Bayreuth, Bayreuth, Germany; 2Technical University of Berlin, Berlin, Germany; 3University of Montpellier 2, Montpellier, France
Metal-organic frameworks offer potential for applications like drug delivery, gas storage and separation as well as sensor design. Such applications rely on interactions between framework and incorporated guests. The guests also interact with framework flexibility, linker disorder and functionalization. The lecture will provide an overview of our results how to introduce and analyze selective host-guest interactions for two framework types - MIL-53 and MIL-101. By combining 1D and 2D multinuclear solid-state NMR spectroscopic experiments including relaxation and hyperfine shifts of paramagnetic systems, we derived preferred binding sites and information about structure, disorder and dynamics of linkers, attached functional groups and adsorbed guests. This finally allowed to determine binding affinities of guests adsorbed at open metal sites and the framework backbone.

Session: Inorganics, time: 4:50-5:05
DNP Surface Enhanced Solid-State NMR at High Field and Fast MAS Using Hybrid Biradicals
Dorothea Wisser1; Arthur Pinon2; Alicia Lund1; Ganesan Karthikeyan3; Gilles Casano3; Florian Bernada3; Maxim Yulikov4; Dominik Kubicki2; David Gajan1; Christophe Copéret4; Gunnar Jeschke4; Moreno Lelli5; Lyndon Emsley2; Olivier Ouari3; Anne Lesage1
1Institut de Sciences Analytiques, Lyon, FR; 2EPFL, Lausanne, CH; 3Aix-Marseille Univ, CNRS, ICR, Marseille, FR; 4ETH, Zurich, CH; 5University of Florence, Florence, IT
Today, the most efficient polarizing agents for solid-state DNP NMR are dinitroxides, which suffer however from an unfavorable field and MAS rate dependence. We have recently introduced new hybrid biradicals tethering a BDPA moiety and a nitroxide and soluble in organic solvents. They are suitable for high magnetic field and very fast MAS DNP enhanced NMR and significantly outperform TEKPol at 18.8 T. In particular, the overall sensitivity gain increases with faster sample rotation. We have applied a source-sink spin diffusion model to explain the MAS dependence of the enhancements at 18.8 T. We will also report DNP-enhanced oxygen-17 Cross Polarization spectra at 18.8 T on silica nanoparticles impregnated with these radicals, yielding surface enhancements of 21.

Session: Inorganics, time: 5:05-5:20
Brønsted/Lewis Acid Synergy in Methanol-to-Aromatics Conversion on Ga-Modified ZSM‐5 Zeolites, As Studied by Solid-State NMR Spectroscopy
Pan Gao; Qiang Wang; Jun Xu; Guodong Qi; Chao Wang; Feng Deng
Wuhan Institute of Physics and Mathematics, Wuhan, China
The importance of the close spatial proximity between metal species and BAS has been widely noted in metal-modified zeolite and a synergic effect is probably present to promote the methanol to aromatics(MTA) reaction. In this work, we investigated the Ga-modified ZSM-5 zeolites with solid state NMR spectroscopy and provided deep insights into the local structure of synergic active sites. The GaO+ ions were observed by the 71Ga QCPMG experiments. 1H−71Ga internuclear spatial proximity/interaction between BAS and cationic Ga species (Lewis acid sites) in Ga-modified ZSM-5 zeolites was identified by the 1H−71Ga double resonance NMR spectroscopy. We also quantified the synergic active sites by the 1H−71Ga double-resonance solid-state NMR, which shows a correlation with the aromatics selectivity in the MTA reaction.

Session: Inorganics, time: 5:20-5:35
: 67Zn NMR Spectroscopy at 35T for Studying Zinc Carboxylates and Deterioration of Paintings.
Nicholas Zumbulyadis1; Xiaoling Wang6; Ivan Hung6; Zhehong Gan2; Yao Yao3; Molly Wagner3; Jaclyn Catalano4; Anna Murphy3; Valeria Di Tullio5; Silvia A. Centeno5; Shi Bai3; Cecil Dybowski3
1Independent Researcher, Rochester, NY; 2NHMFL, Tallahassee, FL; 3University of Delaware, Newark, DE; 4Montclair State University, Montclair, NJ; 5The Metropolitan Museum of Art, New York, NY; 6National High Magnetic Field Laboratory, Tallahassee, FL
Ultra-high magnetic fields enable the study of half-integer quadrupolar nuclei and low-g/low natural abundance nuclides frequently encountered in materials science. 67Zn (I =5/2) has a low gyromagnetic ratio, a natural abundance of 4.1%, and a Cq of several MHz. Zn carboxylates find applications in biochemistry, metallurgy, catalysis, nanotechnology, and MOF-based sensors and selective gas absorbents. We are interested in zinc carboxylates as a major factor in the deterioration of oil paintings and are exploring 67Zn NMR spectroscopy at 36 T to understand the deterioration mechanism. Here we compare the sensitivity gain in going from 19.5T to 35T and compare the Cq values for Zn-octanoate and Zn-palmitate to explore the effect of coordination geometry of zinc carboxylates.

Session: Inorganics, time: 5:35-5:50
Disentangling structure and topology of ordered and disordered solid state materials from dipolar and scalar experiments.
Dominique Massiot1, 2; Valérie Montouillout1, 2; Nadia Pellerin1, 2; Michael Deschamps1, 2; Charlotte Martineau-Corcos1, 3; Pierre Florian1, 2; Vincent Sarou-Kanian1, 2; Aydar Rakhmatullin1, 2; Babacar Diallo1, 2; Franck Fayon1, 2
1CEMHTI-CNRS, Orléans, France; 2Université d'Orléans, Orleans, France; 3Institut Lavoisier de Versailles (ILV), Versailles, France
The challenge is both to measure isotropic and/or anisotropic interactions, to use them efficiently to establish multidimensional correlation experiments and to understand them through DFT based computations. In solid state inorganic materials the difficulty comes with the variety of possible situations involving spin 1/2 and quadrupolar nuclei which remain challenging to measure, especially in the seldom explored case of pairs of quadrupolar spins.