Experiment: 3D HCCH-TOCSY Sample: 2 mM 15N,13C-labeled Ribonuclease T1, (104 a.a.) Experiment time: 16h The 1H-1H (l1=2) and 1H-1H (l1=1) planes of the HCCH-TOCSY spectrum. The 1H-1H (l1=3) and 1H-13C planes of the HCCH-TOCSY spectrum