Related Experiment Video
Updated: Aug 15, 2026

Analyzing and Building Nucleic Acid Structures with 3DNA
Published on: April 26, 2013
H...N hydrogen bond lengths in double stranded DNA from internucleotide dipolar couplings
Z Wu1, A Ono, M Kainosho
1Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0520, USA.
Abstract:
The ratio of the internucleotide dipolar coupling and the corresponding one-bond imino 15N-1H dipolar coupling provides a measure for the N...H/H-N distance ratio. Measurements were carried out for a dodecamer, d(CGCGAATTCGCG)2, in which a C-G and an A-T basepair were uniformly enriched in 15N. When assuming H-bonds to be perfectly linear, dipolar data indicate time-averaged hydrogen bond lengths of 1.80 +/- 0.03 A for A-T and 1.86 +/- 0.02 A for C-G. When using H-bond orientations from high resolution X-ray data, H-bond lengths are about 0.1 A shorter.
Related Concept Videos
Hydrogen Bonds
The DNA Helix
Bond Energies and Bond Lengths
The DNA Helix
¹H NMR: Long-Range Coupling
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene π orbitals.
Hydrogen Bonds

