Measurements of motionally averaged heteronuclear dipolar couplings in MAS NMR using R-type recoupling
- 作者：Dvinskikh ; Sergey V. ; Zimmermann ; Herbert ; Maliniak ; Arnold ; Sandströ ; m ; Dick
- 关键词：Heteronuclear recoupling ; Magic-angle spinning ; SLF ; PDLF ; R-type sequences
- 刊名：Journal of Magnetic Resonance
- 出版年：2004
- 期刊代码：126_10907807
- 类别：ch
- 出版时间：June, 2004
- 卷：168
- 期：2
- 页码：194-201
- 文件大小：300 K
摘要
A novel MAS NMR approach is presented for the determination of heteronuclear dipolar couplings in unoriented materials. The technique is based on the proton-detected local field (PDLF) protocol, and achieves dipolar recoupling by R-type radio-frequency irradiation. The experiment, which is called R-PDLF spectroscopy, is demonstrated on solid and liquid-crystalline systems. For mobile systems, it is shown that the R-PDLF scheme provides better dipolar resolution as compared to techniques combining conventional separated local field (SLF) spectroscopy with R-type recoupling.