Nondestructive high-resolution solid-state NMR of rotating thin films at the magic-angle.

Abstract

We present a new approach to nondestructive magic-angle spinning (MAS) nuclear magnetic resonance (NMR) for thin films. In this scheme, the sample put on the top of a rotor is spun using the conventional MAS system, and the NMR signals are detected with an additional coil. Stable spinning of disk-shaped samples with diameters of 7mm and 12mm at 14.2 and 7kHz are feasible. We present (7)Li MAS NMR experiments of a thin-film sample of LiCoO(2) with a thickness of 200nm. Taking advantage of the nondestructive feature of the experiment, we also demonstrate ex situ experiments, by tracing conformation change upon annealing for various durations. This approach opens the door for in situ MAS NMR of thin-film devices as well.