Enhanced sensitivity in RIACT/MQ-MAS NMR experiments using rotor assisted population transfer.
The rotor assisted population transfer (RAPT) sequence is used to enhance the sensitivity of the RIACT(II) experiment for spin-3/2 quadrupolar nuclei. A detailed theoretical analysis of the polarizations that contribute to different types of MQ-MAS experiments is provided. In particular, two polarization pathways are distinguished for the creation of triple-quantum coherence. The existence of these pathways is experimentally demonstrated by comparing the sensitivities of different sequences with and without RAPT preparation.
Kwak
H T
HT
Department of Chemistry, Ohio State University, Columbus, Ohio 43210-1173, USA.
Prasad
S
S
Yao
Z
Z
Grandinetti
P J
PJ
Sachleben
J R
JR
Emsley
L
L