TY - JOUR
T1 - The use of differential transverse relaxation to detect mobile species in solids
AU - Gerstein, B. C.
AU - Hu, Jian Zhi
AU - Zhou, Jinuan
AU - Ye, Chaohui
AU - Solum, Mark
AU - Pugmire, Ronald
AU - Grant, David M.
N1 - Funding Information:
The Wuhan Group acknowledges the financial support of the National Natural Sciences Foun- dation of China. In addition this work was supported by The Ames Laboratory of the US Department of Energy, Ames, IA 50011, Office of Basic Energy Sciences, Division of Chemical Sciences, under Contract Number W-7405ENG-82, by the Advanced Combustion Engineering Research Center, which is supported by the National Science Foundation and 40 industrial companies, and by the Division of Basic Energy Sciences of the US Department of Energy under Contract Number DE-FG-03-94-ER 14452. We are indebted to Chemagnetics/ Otsuka Electronics, and to Dr. Cindy Ridenour for the NMR spectra of protons in 4-hydroxybenzoic acid.
PY - 1996/2
Y1 - 1996/2
N2 - Delayed acquisition of the proton NMR in selected organic molecular solids (L-alanine, durene, ethyl fumarate, and p-hydroxybenzoic acid) is shown to allow the observation of mobile species in the presence of relatively rigid bulk molecules. The mobility is found to be thermally activated. The combination of the thermally activated motion and magic-angle spinning leads to a fraction of these species moving nearly isotropically on the time scale of the inverse of the homonuclear dipolar splitting. In the case of ethyl fumarate and alanine, there exist populations with differing values of T1 and T1ρ. This indicates the co-existence of relatively rigid and relatively mobile molecules in the same sample. The intensities under delayed acquisition cannot always be trusted to yield quantitative information. Comparison of spectra taken under delayed acquisition and under the CRAMPS (B.C. Gerstein, R.G. Pembleton, R.C. Wilson and L.M. Ryan, J. Chem. Phys., 66 (1977) 361) technique is made.
AB - Delayed acquisition of the proton NMR in selected organic molecular solids (L-alanine, durene, ethyl fumarate, and p-hydroxybenzoic acid) is shown to allow the observation of mobile species in the presence of relatively rigid bulk molecules. The mobility is found to be thermally activated. The combination of the thermally activated motion and magic-angle spinning leads to a fraction of these species moving nearly isotropically on the time scale of the inverse of the homonuclear dipolar splitting. In the case of ethyl fumarate and alanine, there exist populations with differing values of T1 and T1ρ. This indicates the co-existence of relatively rigid and relatively mobile molecules in the same sample. The intensities under delayed acquisition cannot always be trusted to yield quantitative information. Comparison of spectra taken under delayed acquisition and under the CRAMPS (B.C. Gerstein, R.G. Pembleton, R.C. Wilson and L.M. Ryan, J. Chem. Phys., 66 (1977) 361) technique is made.
KW - Differential transverse relaxation
KW - Mobile species
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U2 - 10.1016/0926-2040(95)01211-7
DO - 10.1016/0926-2040(95)01211-7
M3 - Article
C2 - 8925267
AN - SCOPUS:0030076077
SN - 0926-2040
VL - 6
SP - 63
EP - 71
JO - Solid State Nuclear Magnetic Resonance
JF - Solid State Nuclear Magnetic Resonance
IS - 1
ER -