Ferromagnetic fullerene

Abstract

New magnetic forms of C60 have been identified which occur in the rhombohedral polymer phase. The existence of previously reported ferromagnetic rhombohedral C60 is confirmed. This property has been shown to occur over a range of preparation temperatures at 9 GPa. The structure is shown to be crystalline in nature containing whole undamaged buckyballs. Formation of radicals is most likely due to thermally activated shearing of the bridging bond resulting in dangling bond formation. With increasing temperatures this process occurs in great enough numbers to trigger cage collapse and graphitization. The magnetically strongest sample was formed at 800 K, and has a saturated magnetization at 10 K, in fields above 3 kOe, of 0.045 emu g-1.

Half-Metallic Zigzag Carbon Nanotube Dots

“…We have studied a set of sixteen finite segments of the (7,0), (8,0), (9,0), and (10,0) zigzag CNTs (see Fig. 1).…”

Spin-transfer mechanism of ferromagnetism in polymerized fullerenes:Ab initiocalculations

“…2 More recently, room temperature ferromagnetism has been reported in fullerenes polymerized by means of photo-processes 4,5,6 and by high pressure -high temperature treatment 7,8,9,10 and hydrofullerites. 13 In the present paper, we focus our attention on the problem of the high temperature magnetism in polymerized fullerenes.…”

“…Recent developments in material science have resulted in the discovery of a novel class of magnetic organic materials based on carbon, such as fullerenes 1,2,3,4,5,6,7,8,9,10 and graphite. 11,12 Fullerenes C 60 intercalated with the organic TDAE-molecule is ferromagnetic below 16 K.…”

Theoretical Studies on Electronic States of Rh-C60. Possibility of a Room-temperature Organic Ferromagnet

“…However, as mentioned above, experimental results, conductivity mitigate against this mechanism since the 'dangling bond' associated with an sp 3 hybridised facial C indicates strong localization of the electron on pristine C 60 , while the observed conductivity indicates itinerant behaviour. Production of magnetic domains in Rh-C 60 was independently reported by another group [14]. Wood et al synthesized polymerized Rh-C 60 in the region 700~1200 K under 9 GPa pressure.…”