Unravelling the Mystery of Solid Solutions: A Case Study of ⁸⁹Y Solid‐State NMR Spectroscopy

Abstract

Incorporating heteroatoms in functional materials is an invaluable approach to modulate their properties, assuming a solid solution is formed. However, thorough understanding of key structural information on the resulting solid solution, such as the local environment of cations and vacancies, remains a challenge. Solid-state NMR (SSNMR) spectroscopy is a powerful structural characterization tool, very sensitive to the local environment. Due to the difficulty in signal acquisition and spectral interpretation, SSNMR spectroscopy is relatively less known to chemists and materials scientists. Herein, we present an introductory review to demonstrate how to use 89 Y SS NMR spectroscopy to unravel the mystery of solid solutions. In general, 89 Y chemical shift varies with different cation/vacancy arrangements in Y coordination spheres, providing ultrafine structural information in the atomic scale. As a case study and an extreme condition, the approach demonstrated in this review can be extended to other systems.[a] Prof.

Investigation of Intermetallic Energy Transfers in Lanthanide Coordination Polymers Molecular Alloys: Case Study of Trimesate-Based Compounds

“…However, the large chemical shift range of 89 Y NMR allows identifying subtle changes in the local environment of the yttrium ions. Solid-state NMR 89 Y forms an emerging tool for the characterization of local ordering in lanthanide molecular alloy compounds …”

“…Solid-state NMR 89 Y forms an emerging tool for the characterization of local ordering in lanthanide molecular alloy compounds. 72 89 Y spectra were recorded using a 90°simple pulse sequence. The recycle delay was set to 60 s. In an attempt to increase the S/N ratio, we evaluated the effect of proton decoupling (12 kHz) and cross-polarization transfer from 1 H to 89 Y.…”

“X Factor” in the Structure and Anion Exchange of Layered Yttrium Hydroxides

“…In general, the 89 Y isotropic chemical shift (δ iso ) value increases with the decreasing coordination number . The first group is therefore assigned to the eight-coordinated Y1 site in the P 2 1 2 1 2 structure, whereas the others must correspond to the nine-coordinated Y2 and Y3 sites.…”

“…The LYH-X (X − = Cl − , Br − , NO 3 − ) family was selected because (i) this family has been extensively used and studied, (ii) these compounds can be obtained in various X − forms with low cost, and (iii) 89 Y SSNMR spectroscopy is very sensitive to local Y environment due to its high spectral resolution (I = 1/2) and large chemical shift range (∼1000 ppm), by which fine structural details can be extracted. 54 The sensitivity issue of 89 Y SSNMR arising from the low gyromagnetic ratio and slow longitudinal relaxation rate of 89 Y can be easily mitigated by performing 1 H− 89 Y cross-polarization (CP) experiments. 55 In this work, all 89 Y NMR spectra were collected with the implemented CP technique.…”

“…5 In general, the 89 Y isotropic chemical shift (δ iso ) value increases with the decreasing coordination number. 54 The first group is therefore assigned to the eight-coordinated Y1 site in the P2 1 2 1 2 structure, whereas the others must correspond to the nine-coordinated Y2 and Y3 sites. To distinguish the two Y sites, DFT calculations under periodic boundary conditions were performed as a reliable approach for interpreting and assigning NMR data.…”