New Insights into the Short-Range Structures of Microporous Titanosilicates As Revealed by <sup>47/49</sup>Ti, <sup>23</sup>Na, <sup>39</sup>K, and <sup>29</sup>Si Solid-State NMR Spectroscopy XuJun E. G. LucierBryan LinZhi SutrisnoAndre TerskikhVictor V. HuangYining 2014 Seven prototypical microporous titanosilicates have been studied by multinuclear solid-state NMR (SSNMR) spectroscopy, representing four typical Ti environments: square-pyramidal TiO<sub>5</sub> units (natisite, AM-1, ETS-4), edge-shared brookite-type TiO<sub>6</sub> chains (AM-4), cubane-type Ti<sub>4</sub>O<sub>16</sub> clusters (sitinakite, GTS-1), and corner-shared TiO<sub>6</sub> chains (ETS-10, ETS-4). <sup>47/49</sup>Ti SSNMR spectra at 21.1 T are related to the coordination, crystal symmetry, and local environment of Ti. Distortions in Ti–O bond lengths and O–Ti–O coordination angles are reflected via <i>C</i><sub>Q</sub>(<sup>47/49</sup>Ti) values that range from 8 to 16 MHz. Several titanosilicates feature axially symmetric <sup>47/49</sup>Ti electric field gradient (EFG) tensors that permit facile spectral assignment and detection of deviations in local symmetry. This study uses <sup>29</sup>Si NMR experiments to assess phase purity and crystallinity. <sup>23</sup>Na NMR is used to probe the location and mobility of the sodium ions in the framework. The potential of <sup>39</sup>K SSNMR for investigation of extra-framework counter cations is demonstrated by ETS-10, with increased spectral resolution and enhanced sensitivity to changes in local environment versus <sup>23</sup>Na experiments. Plane-wave DFT calculations predicted <sup>47/49</sup>Ti NMR parameters assisting in spectral assignments and help correlate <sup>23</sup>Na and <sup>29</sup>Si NMR resonances to crystallographic sites. The approach described in this work should promote further SSNMR investigations of microporous solids, such as titanosilicates, with unknown or poorly defined structures.