As there is only one strong peak for the classical amide III vibration, cross-peaks between the amide III vibrations are hardly visible. Similarly, there are only very weak peaks for the C α -H bending vibrations, and cross-peaks between classical amide III and C α -H bending vibrations are similarly weak. For the β-strand, both the classical amide III vibrations and the C α -H bending show strong signals on the diagonal. Here, the cross-peaks between the classical amide III vibrations are rather weak, while there are strong cross-peaks between the classical amide III and the C α -H bending vibrations. This pattern is preserved for the βsheet model (consisting of two antiparallel β-strands), even though the cross-peaks between the classical amide III vibrations gain some intensity. Overall, this is in qualitative agreement with the dipeptide model and indicates that the identified signatures for distinguishing α-helical and β-strand structures could be transferable to larger systems.