The Effect of Intermolecular Halogen Bond on 19F DNP Enhancement in 1, 4-Diiodotetrafluorobenzene/4-OH-TEMPO Supramolecular Assembly

• Main Authors: GAO Shan, HUANG Chong-yang, ZHANG Zhen, CHEN Jun-fei, HE Yu-gui, CHEN Li, CHEN Fang, ZHANG Jin-zhi, LIU Chao-yang
• Format: Article
• Language: zho
• Published: Science Press 2017-12-01
• Series: Chinese Journal of Magnetic Resonance
• Subjects: 19F DNP; halogen bond; DITFB/4-OH-TEMPO; DNP enhancement
• Online Access: http://html.rhhz.net/bpxzz/html/20170403.htm

Halogen bond, as hydrogen bond, is a non-covalent bond. Dynamic nuclear polarization (DNP) technique has been used previously to study hydrogen bonds-mediated intermolecular interactions. However, no study has been carried out so far to study the halogen bond-mediated intermolecular interactions with DNP. In this work, 19F DNP polarization efficiency of the halogen bonds existing in supramolecular assembling by 4-OH-TEMPO and 1,4-diiodotetrafluorobenzene (DITFB) was studied on a home-made DNP system. The formation of intermolecular halogen bonds appeared to increase 19F DNP polarization efficiency, suggesting that the spin-spin interactions among electrons were weakened by the halogen bonds, resulting in an increased T2e and a larger saturation factor.