Icosahedral quasi-crystals were studied by using 27Al 2-dimensional exchange nuclear magnetic resonance methods. The results revealed slow atomic motions in the sub-kHz range, at temperatures of between 0.16 and 130K. The observed motion was limited in space and was associated with local phason fluctuations at very low energies which involved quantum tunnelling at very low temperatures. It was regarded as being an atomic motion that acted as a precursor to bulk self-diffusion.

Atomic Motion in Quasicrystalline Al70Re8.6Pd21.4: a Two-Dimensional Exchange NMR Study J.Dolinšek, B.Ambrosini, P.Vonlanthen, J.L.Gavilano, M.A.Chernikov, H.R.Ott: Physical Review Letters, 1998, 81[17], 3671-4