Influence of the guest molecule on the rotational motions of ammonia groups in Hofmann clathrates

INS experiments on Hofmann clathrates NiNiG with various guest molecules G give rotational level schemes for NH ₃ in NiNiC ₆H ₆ and NiNiC ₁₂H ₁₀ identical with those in NiNiC ₆D ₆. For polar guest molecules, tunnelling transitions indicative for moderately strong hindering potentials are observed.