Details

Autor(en) / Beteiligte

• Carravetta, M.
• Johannessen, O. G.
• Levitt, M. H.
• Heinmaa, I.
• Stern, R.
• Samoson, A.
• Horsewill, A. J.
• Murata, Y.
• Komatsu, K.

Titel

Cryogenic NMR spectroscopy of endohedral hydrogen-fullerene complexes

Ist Teil von

• The Journal of chemical physics, 2006-03, Vol.124 (10), p.104507-104507-13

Ort / Verlag

United States: American Institute of Physics

Erscheinungsjahr

2006

Quelle

AIP Journals Complete

Beschreibungen/Notizen

• We have observed H 1 NMR spectra of hydrogen molecules trapped inside modified fullerene cages under cryogenic conditions. Experiments on static samples were performed at sample temperatures down to 4.3 K , while magic-angle-spinning (MAS) experiments were performed at temperatures down to 20 K at spinning frequencies of 15 kHz . Both types of NMR spectra show a large increase in the intramolecular H 1 - H 1 dipolar coupling at temperatures below 50 K , revealing thermal selection of a small number of spatial rotational states. The static and MAS spectra were compared to estimate the degree of sample heating in high-speed cryogenic MAS-NMR experiments. The cryogenic MAS-NMR data show that the site resolution of magic-angle-spinning NMR may be combined with the high signal strength of cryogenic operation and that cryogenic phenomena may be studied with chemical site selectivity.