by Keyword: Radical-pair
Chuchkova, L, Bodenstedt, S, Picazo-Frutos, R, Eills, J, Tretiak, O, Hu, YA, Barskiy, DA, de Santis, J, Tayler, MCD, Budker, D, Sheberstov, KF, (2023). Magnetometer-Detected Nuclear Magnetic Resonance of Photochemically Hyperpolarized Molecules Journal Of Physical Chemistry Letters 14, 6814-6822
Photochemically induced dynamic nuclear polarization (photo-CIDNP) enables nuclear spin ordering by irradiating samples with light. Polarized spins are conventionally detected via high-field chemical-shift-resolved NMR (above 0.1 T). In this Letter, we demonstrate in situ low-field photo-CIDNP measurements using a magnetically shielded fast-field-cycling NMR setup detecting Larmor precession via atomic magnetometers. For solutions comprising mM concentrations of the photochemically polarized molecules, hyperpolarized 1H magnetization is detected by pulse-acquired NMR spectroscopy. The observed NMR line widths are about 5 times narrower than normally anticipated in high-field NMR and are systematically affected by light irradiation during the acquisition period, reflecting a reduction of the transverse relaxation time constant, T2*, on the order of 10%. Magnetometer-detected photo-CIDNP spectroscopy enables straightforward observation of spin-chemistry processes in the ambient field range from a few nT to tens of mT. Potential applications of this measuring modality are discussed.
JTD Keywords: field-dependence, mechanism, nmr, parahydrogen, photo-cidnp, polarization, quinone, spin-hyperpolarization, Radical-pair
