Standard chemical shifts of random extended chain structures:

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¹H chemical shifts of amino acids

¹³C chemical shifts of amino acids

Average ¹HA, ¹HN and ¹⁵N chemical shifts in random coil

Easy spin system identification from:

• HA-HB cross-peak in a  COSY-DQF experiment.
• Typical AMX pattern in a TOCSY experiment.

Standard average chemical shift values used in determination of secondary structure by means of the CSI method:

HA: 4.76
CA: 53.9
CO: 176.8

Thus:

          HELIX           B STRAND          COIL
             CA      CO       CA      CO           CA      CO
            56.7    177.9     52.3    176.0      54.2    176.8

More info in: ¹³CA and ¹³CO chemical shifts according to secondary structure.