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arXiv · 1307.0832

Preparation of Nuclear Spin Singlet States using Spin-Lock Induced Crossing

Stephen J. DeVience·Ronald L. Walsworth·Matthew S. Rosen
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Abstract

We introduce a broadly applicable technique to create nuclear spin singlet states in organic molecules and other many-atom systems. We employ a novel pulse sequence to produce a spin-lock induced crossing (SLIC) of the spin singlet and triplet energy levels, which enables triplet/singlet polarization transfer and singlet state preparation. We demonstrate the utility of the SLIC method by producing a long-lived nuclear spin singlet state on two strongly-coupled proton pairs in the tripeptide molecule phenylalanine-glycine-glycine dissolved in D2O, and by using SLIC to measure the J-couplings, chemical shift differences, and singlet lifetimes of the proton pairs. We show that SLIC is more efficient at creating nearly-equivalent nuclear spin singlet states than previous pulse sequence techniques, especially when triplet/singlet polarization transfer occurs on the same timescale as spin-lattice relaxation.

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Stephen J. DeVience, Ronald L. Walsworth, Matthew S. Rosen. 2013-07-02. Preparation of Nuclear Spin Singlet States using Spin-Lock Induced Crossing. https://doi.org/10.1103/physrevlett.111.173002

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