Singlet fission as a polarized spin generator for dynamic nuclear polarization

Singlet fission (SF), converting a singlet excited state into a spin-correlated triplet-pair state, is an effective way to generate a spin quintet state in organic materials. This study demonstrates that the spin polarization of quintet multiexcitons generated by SF improves the sensitivity of magnetic resonance of water molecules through dynamic nuclear polarization (DNP). Supramolecular assemblies of pentacene chromophores were used to achieve DNP of water-glycerol, showing a dependence of nuclear polarization enhancement on magnetic field and microwave power. This work opens the use of SF as a polarized spin generator in bio-quantum technology.

Yusuke Kawashima, Tomoyuki Hamachi, Akio Yamauchi, Koki Nishimura, Yuma Nakashima, Saiya Fujiwara, Nobuo Kimizuka, Tomohiro Ryu, Tetsu Tamura, Masaki Saigo, Ken Onda, Shunsuke Sato, Yasuhiro Kobori, Kenichiro Tateishi, Tomohiro Uesaka, Go Watanabe, Kiyoshi Miyata, Nobuhiro Yanai