Triplet dynamic nuclear polarization of crystalline ice using water-soluble polarizing agents.

Triplet dynamic nuclear polarization (triplet-DNP) allows hyperpolarization at a moderate temperature. While the triplet-DNP of water is strongly desired, water-soluble triplet polarizing agents have not yet been reported. Herein, the first example of triplet-DNP of crystalline ice is demonstrated by molecularly dispersing a novel water-soluble polarizing agent into ice.