Nuclear Magnetic Resonance Studies of Interfacial Phenomena

"Preface Properties of high surface area materials and their efficiency of application strongly depend on boundary effects and interfacial phenomena. These phenomena include diffusion of adsorbate and solvent molecules at the surface of the adsorbent, physisorption and chemisorption, dissolution, so [...]
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"Preface Properties of high surface area materials and their efficiency of application strongly depend on boundary effects and interfacial phenomena. These phenomena include diffusion of adsorbate and solvent molecules at the surface of the adsorbent, physisorption and chemisorption, dissolution, solvation of solutes and solid surfaces, surface reactions, heterogeneous catalysis, relaxation and segmental dynamics of adsorbed macromolecules, phase transitions, crystallization, and melting, among others. Many of the physicochemical characterization methods give very useful and complementary information regarding complex interfacial phenomena. These methods include nuclear magnetic resonance (NMR) spectroscopy, infrared (FTIR) and other optical spectroscopic methods, differential scanning calorimetry (DSC), adsorption of probe compounds, x-ray diffraction (XRD), Auger electron spectroscopy, ultrasoft x-ray emission spectroscopy, x-ray photoelectron spectroscopy (XPS), dielectric relaxation spectroscopy (DRS), and thermally stimulated depolarization current (TSDC), among others. Among these, NMR spectroscopy is the most universal, yielding very detailed structural information regarding molecules, solids, and interfaces. NMR provides information on molecular diffusion, phase transitions, melting, crystallization, relaxation, adsorption, reaction kinetics, and so on. There are a number of NMR techniques for measuring pore sizes, the two main being NMR cryoporometry, which is based on the pore-size dependence of the melting temperature of a mobile phase, and NMR relaxometry, which is based on transverse relaxation times that are sensitive to confined-space effects"--