Characterization of very fast motions in solid peptides by solid-state nitrogen-14 NMR

Experimental double-quantum 14N/1H correlation spectrum of the -NH3 group (I) and the two rigid amide NH pairs (II) in the tripeptide Ala-Ala-Gly. The 2.5 mm rotor was spun at 29.76 kHz in a static field of 18.8 T at 49 °C. (d, f) Experimental cross sections parallel to the vertical dimension of the double-quantum spectrum of sites I and II. (e,g) Simulated double-quantum spectra of sites I and II.

Simulations of the line width of single-quantum 14N spectra as a function of the exchange rate 102 < k < 108 s-1, assuming two-site jumps.

Related publications

• Evidence for Dynamics on a 100 ns Time-Scale from Single- and Double-Quantum Nitrogen-14 NMR in Solid Peptides. S. Cavadini, A. Abraham, S. Ulzega, and G. Bodenhausen, J. Am. Chem. Soc. 130, 10850-10851 (2008).