. Author manuscript; available in PMC: 2009 Dec 10.

Published in final edited form as: J Am Chem Soc. 2008 Dec 10;130(49):16518–16520. doi: 10.1021/ja805654f

Table 1.

Average dynamics parameters and amide N-H bond lengths (Å).

	r_NH^eq^a	r_eff^b	<r_NH> ^c	S′_NH	σ_tr^g	S′_C′HN^h
this work ^d	1.008 ± 0.006	1.015 ± 0.006	1.023 ± 0.006	0.910 ± 0.016	9.9° ± 0.9°	0.981 ± 0.004
Others			1.022^e	0.938^f	8.2°^f	0.994^f

r_eq is the equilibrium bond length;

r_eff = <r_NH^-3>^-1/3, where <…> denotes the bond stretching average;

<r> is the stretching-averaged bond length with the difference between r_eq and <r> resulting from anharmonicity;

Uncertainty in the averaged value based on jackknife analysis;

<r_NH> from neutron scattering¹;

Value for N-H zero point libration in N-methylacetamide, obtained from MP2 quantum calculation, divided by the corresponding S_CαC′ value of 0.990.

σ_tr = (σ_u² + σ_v²)^1/2.

S′_C′HN is the C′-H^N order parameter relative to the C^α-C′-N backbone.