Observation of scalar nuclear spin–spin coupling in van der Waals complexes

http://www.pnas.org/content/109/31/12393.short?rss=1

1. Micah P. Ledbetter, 
2. Giacomo Saielli, 
3. Alessandro Bagno,
4.  Nhan Tran, and 
5. Michael V. Romalis

Scalar couplings (J-couplings) between covalently bound nuclei are commonly observed in NMR spectra. However, the authors claim to be the first to report observations of scalar couplings of non-covalently bound van der Waals complexes between hyperpolarized, chilled xenon and pentane. They measure proton frequency shifts that are the result of scalar couplings with hyperpolarized xenon. Their measurements agree with DFT calculations.