Molecular dynamics in aluminum layered double hydroxides as studied by 1H T1ρ NMR measurements

Proton dynamics in pristine and organically-modified layered double hydroxide has been studied by 1H T1ρ. Inverse Laplace transform with spectral resolution results in a correlation of T1ρ and chemical shift. two contributions are resolved. They are assigned to the metal hydroxides, forming the LDH sheets (4–8 ms), and mobile interlayer water (2 ms). Apparent T1ρ values of OH-protons in surfactant-modified LDH are different in dodecylbenzenesulfonate- (SDBS) and sodium octasulfonate- (C8) modified LDH. This difference is explained by the presence of water in LDH–SDBS. The effects of spin diffusion have been studied by performing 2D 1H RFDR in the LDH–SDBS.