Nuclear magnetic resonance relaxation in nucleic acid fragments: models for internal motion

Abstract
A variety of models incorporating internal motion, which can be used to extract information from NMR relaxation studies of DNA fragments, are formulated. Illustrative analyses of some recent multinuclear relaxation data are presented. Special emphasis is placed on determining whether the information extracted is unique. The data are consistent with several physical pictures of the internal motion. All the models considered imply the existence of large-amplitude internal motions on the nanosecond time scale.