In developing the approach to understanding dynamics of intercalates in layered materials, crystalline-layered zirconium phosphate Zr (HPO 4 ) 2 Á0.35D 2 O has been prepared and characterized by the 1 H, 31 P, and 2 H solid-state MAS NMR spectra, including 31 P and 2 H T 1 measurements. At temperatures >253 K, the intercalated water shows two spectrally-distinguished deuterons unprecedentedly with different DQCC's and 2 H T 1 times, one of which is hydrogen bonded. The collected data allowed to identify an unexpected bonding/dynamic mode of water molecules, which experience fast rotation around the hydrogen bond, formed with a zirconium-coordinated oxygen. The lowtemperature 2 H MAS NMR experiments have demonstrated the presence of additional hydrogen bond P (H)O˙˙˙DO, population of which grows on cooling to 195 K corresponding to the doubly hydrogen-bonded immobile water molecule.

We show how the structural order of nanocrystalline zirconium phosphates (ZrP) is tuned by the synthetic methods and conditions through the use of synchrotron X-ray atomic pair distribution function analysis. With different synthetic route and different phosphoric acid concentrations in the synthesis, the product zirconium phosphates vary from turbostratically disordered nanoscale structures to fully ordered ones. We show that a change in the structural order leads to different ion-exchange properties. The samples are characterized using multiple techniques, including powder X-ray diffraction, ion exchange, thermogravimetric analysis, transmission electron microscopy, fast neutron activation analysis, solid-state NMR spectroscopy, IR spectroscopy, and X-ray photoelectron spectroscopy.

Solid‐state NMR experiments on 2H, 31P, 13C, and 1H nuclei, including 31P T1, 1H T1, and 1H T1ρ measurements, as well as on the kinetics of proton‐phosphorus cross‐polarization have been performed to characterize the crystalline and amorphous α‐zirconium phosphates, which were intercalated with D2O and/or CD3OD. The 13C{1H} CP MAS NMR experiment performed for compound 1‐CD3OD (Zr (HPO4)2.0.2CD3OD) with carbon cross‐polarization via protons of phosphate groups has provided a prove that the methanol was intercalated into the interlayer spaces of this compound. The variable‐temperature 2H solid‐echo MAS NMR spectra of intercalated compounds demonstrated that the methanol molecules, in contrast to the mobile water, were immobile, keeping, however, free CD3 rotations around the C3‐axis. It has been demonstrated that the intercalated species, D2O and CD3OD, do not affect the high‐frequency motions of the phosphate groups. By utilizing local structural models that satisfy the constraints of the experimental data, it has been suggested that the immobile methanol molecules are located in the cavity between two neighboring layers of the zirconium phosphates. Thus, the present work illustrates the reliable criteria in a comprehensive NMR approach to structural and dynamic studies of such systems.

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