Moments of the Power Spectra of Dipolar Interaction between Spin-12 Nuclei

✍ Scribed by Günter Hempel; Ulf Schmeißer

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 164 KB
• Volume: 121
• Category: Article
• ISSN: 1064-1858
• DOI: 10.1006/jmra.1996.0134

✦ Synopsis

The evaluation of the second moment from dipolar-broadened

The use of high-resolution proton spectra [ multipulse lines leads to a higher degree of reproducibility if the power specsequences, CRAMPS ( 3 ) ] is complicated since liquidtrum is used. Very small deviations in the baseline far away from crystalline macromolecules contain many chemically difthe center of the line caused by small phase differences are an ferent protons. If their resonances overlap severely, the important reason for poor reproducibility of second moments of evolution of the orientation state can hardly be obtained absorption-mode spectra. This paper shows that, in the case of from the spectra. dipolar interaction of spins I Å 1 2 , the second moment of the power Orientation state and order parameter in liquid crystals spectrum depends on geometrical parameters in the same way as are often characterized by dipolar splitting if it is measurable the real-part second moment does. However, there is no trivial with sufficient accuracy (4, 5). However, if the process of general relation between the moments of absorption and power the rotation of the director field in polymeric liquid crystals is spectra.