Vitzthum, V., et al., Dynamic nuclear polarization of quadrupolar nuclei using cross polarization from protons: surface-enhanced aluminium-27 NMR. Chemical Communications, 2012. 48(14): p. 1988-1990.
The surface of [gamma]-alumina nanoparticles can be characterized by dynamic nuclear polarization (DNP) surface-enhanced NMR of 27Al. DNP is combined with cross-polarization and MQ-MAS to determine local symmetries of 27Al sites at the surface.