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Updated: Aug 2, 2026

Molecular Entanglement and Electrospinnability of Biopolymers
Published on: September 3, 2014
The presence of long-lived spin states in organic solids with rapid molecular motions
1Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019-3051, USA. bmfung@ou.edu
Abstract:
For organic solids with sufficiently mobile molecular segments, the application of a long and weak pulse (gammaB1/2pi approximately Hz) can yield inverted sharp peaks with linewidths of approximately 100 Hz in the 1H NMR spectra, and the use of multi-frequency weak pulses can excite multiple inverted sharp peaks. For these compounds, the normal 1H free induction decay (FID) of a static sample contains a slowly decaying part, which can be detected by acquisition delay up to about 2 ms. The presence of highly mobile molecular segments can also be identified by using a "dipolar filter."
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