Implementing solenoid microcoils for wide-line solid-state NMR.

K Yamauchi; J W G Janssen; A P M Kentgens

doi:10.1016/j.jmr.2003.12.003

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Implementing solenoid microcoils for wide-line solid-state NMR.

K Yamauchi·J W G Janssen·A P M Kentgens

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Abstract

Solid-state nuclear magnetic resonance (NMR) probeheads using solenoid microcoils with an inner diameter of 300-400 microm are developed for the study of mass-limited solid samples. Some attention is paid to the mechanical ruggedness of the probes allowing sample changing. The performance, in terms of sensitivity and RF-characteristics, of these probeheads is studied for (1)H, (31)P, and (27)Al in different model compounds in view of the feasibility of specific applications. The results show that the sensitivity is high enough to detect approximately 10(14) spins/sqrt Hz with a signal-to-noise ratio of 1 in a single scan. A specific advantage of microcoils for solid-state NMR applications is that they can generate extremely high RF-fields if implemented in appropriate circuits. Using RF-powers in the hundreds of Watts range, RF-fields well in excess of 1MHz can be made. This allows the excitation of spectra of nuclei whose resonance lines are dispersed of several megahertz. This is particularly useful for quadrupolar nuclei experiencing large quadrupolar interactions as is demonstrated for (27)Al in single crystal and powdered minerals.

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Computer-Aided Design Dimethylpolysiloxanes Equipment Design Equipment Failure Analysis Magnetic Resonance Spectroscopy Magnetics Minerals Reproducibility of Results Sensitivity and Specificity Silicones Transducers Comparative Study Evaluation Study Journal Article Research Support, Non-U.S. Gov't

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K Yamauchi, J W G Janssen, A P M Kentgens. 2004. Implementing solenoid microcoils for wide-line solid-state NMR.. https://doi.org/10.1016/j.jmr.2003.12.003

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