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arXiv · 2207.03446

Polychromatic Excitation of Delocalized Long-Lived Proton Spin States in Aliphatic Chains

Anna Sonnefeld·Geoffrey Bodenhausen·Kirill Sheberstov
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Abstract

Long-lived states (LLS) involving pairs of magnetically inequivalent but chemically equivalent proton spins in aliphatic (CH$_2$)$_n$ chains can be excited by simultaneous application of weak selective radio-frequency (RF) fields at n chemical shifts by polychromatic spin lock induced crossing (poly-SLIC). The LLS are delocalized throughout the aliphatic chain by mixing of intrapair singlet states and by excitation of LLS comprising products of four or six spins. The measured lifetimes T$_{LLS}$ in a model compound are about 5 times longer than T1, and are strongly affected by interactions with macromolecules.

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Anna Sonnefeld, Geoffrey Bodenhausen, Kirill Sheberstov. 2022-07-07. Polychromatic Excitation of Delocalized Long-Lived Proton Spin States in Aliphatic Chains. https://doi.org/10.1103/physrevlett.129.183203

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