Signal enhancement in 5QMAS spectra of spin-5/2 quadrupolar nuclei

被引：23

作者：

Goldbourt, A ^{[1
]}

Vega, S ^{[1
]}

机构：

[1] Weizmann Inst Sci, IL-76100 Rehovot, Israel

来源：

JOURNAL OF MAGNETIC RESONANCE | 2002年 / 154卷 / 02期

关键词：

solid state NMR; MQMAS; FAM; quadrupolar nuclei; sensitivity enhancement;

D O I：

10.1006/jmre.2001.2475

中图分类号：

Q5 [生物化学];

学科分类号：

071010 ; 081704 ;

摘要：

5QMAS experiments on spin-5/2 systems display a low sensitivity compared with their 3QMAS counterparts. Nevertheless, the superior resolution of 5QMAS over 3QMAS makes these experiments a favorable choice for many materials. We report an enhancement scheme for the 5QMAS experiment, using an improved five-quantum excitation pulse scheme combined with a FAM-II conversion pulse. The results are verified experimentally on a polycrystalline sample of gamma-(Al2O3)-Al-27, showing an enhancement factor of 2.4 over the simple two-pulse (CW) 5QMAS scheme. Numerical computations of the efficiency parameter epsilon support these results. (C) 2002 Elsevier Science (USA).

引用

页码：280 / 286

页数：7

共 36 条

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