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Updated: Aug 10, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
LR-CAHSQC: an application of a Carr-Purcell-Meiboom-Gill-type sequence to heteronuclear multiple bond correlation
Harri Koskela1, Ilkka Kilpeläinen, Sami Heikkinen
1Department of Chemistry, University of Oulu, PO Box 3000, Oulu FIN-90014, Finland. Harri.Koskela@oulu.fi
Abstract:
A new pulse sequence, long-range CPMG-adjusted heteronuclear single quantum coherence (LR-CAHSQC), is proposed for the determination of long-range JCH coupling constants from a long-range 1H-13C correlation experiment. The long-range heteronuclear coupling constants can be directly extracted from COSY-type antiphase peak patterns. The current approach utilizes CPMG-sequences for polarization transfer, and thus avoids the evolution of homonuclear JHH couplings, which normally may introduce abnormalities into the cross peak pattern. The differences between LR-CAHSQC and normal LR-HSQC are discussed.
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