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:

• Very typical NH-HA-HA' cross-peak in 2D COSY-DQF and TOCSY experiments.
• Experiments to selectively observe gly in labeled proteins: 93JMRB214-101 , 99JMR15-126

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

HA: 3.97
CA: 45.0
CO: 173.6

Thus:

          HELIX              B STRAND
             CA      CO            CA      CO
            46.5    175.5        44.6    171.9

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