Table 1.
Anisotropy and magic angle intensity (measured from the top to the bottom) of all identified cross peaks and diagonal peaks in the 2D-IR spectrum of the peptide
| Pump | Probe
|
||||
|---|---|---|---|---|---|
| 1,673 cm−1 | 1,648 cm−1 | 1,620 cm−1 | 1,610 cm− | 1,584 cm−1 | |
| 1,648 cm−1 | 0.05 ± 0.5 | 0.35 ± 0.05 | 0.2 ± 0.3† | 0.09 ± 0.05 | |
| 0.04 mOD | 0.52 mOD | 0.06 mOD | 0.03 mOD | ||
| 1,620 cm−1 | – | 0.15 ± 0.05 | 0.36 ± 0.05 | – | 0.05 ± 0.02 |
| – | 0.03 mOD | 0.54 mOD | – | 0.15 mOD | |
| 1,610 cm−1 | – | 0.25 ± 0.05 | –† | 0.38 ± 0.05 | 0.11 ± 0.02 |
| – | 0.03 mOD | – | 0.52 mOD | 0.16 mOD | |
| 1,584 cm−1 | – | – | 0.06 ± 0.05* | 0.11 ± 0.02 | 0.36 ± 0.05 |
| – | 0.03 mOD | 0.07 mOD | 0.11 mOD | 0.39 mOD | |
The experimental errors in the magic angle intensities is ca. ± 0.01 milli optical density units (mOD).
*
Only the negative signal of this band was used, because the positive part overlaps with the stronger contribution from the 1,610 cm−1 transition.
†
Because of the small frequency separation, no clear distinction between the two bands could be made.