An NMR investigation on the adducted hydrogen in weak ferromagnetic rhombohedral C60 polymers

• DOI: 10.1016/j.cplett.2009.09.070
• Publication Date: 2009-09-24T10:24:00Z
• Authors: Yao Yu; Jianbao Wu; Min Gu; Weiyi Zhang; Guanglei Cui; Xibin Xu; Duan Feng; Tong Bor Tang
• Keywords: 0103 physical sciences; 01 natural sciences

Abstract The fact that a magnetic hysteresis loop is observed only in polymerized C 60 and is absent in both pristine and depolymerized C 60 establishes a close link between the weak ferromagnetism and the underlying structure. Furthermore, the correlation between the weak ferromagnetism and hydrogen presence has been explored by 1 H NMR and 1 H– 13 C cross-polarization NMR, whereby strong bonding between the H adducts and C 60 has been verified. The adducted hydrogens most likely form bonds with the carbon atoms of inter-C 60 four-membered rings. This conclusion is further supported by the formation energy of adducted H and the exchange energy among adducted H obtained from first-principle calculations on Rh-C 60 .