We have investigated spin related processes in fullerene C 60 devices using several experimental techniques, which include magnetic field effect of photocurrent and electroluminescence in C 60 -based diodes; spin polarized carrier injection in C 60 -based spin-valves; and pure spin current generation in NiFe/C 60 /Pt trilayer devices. We found that the ‘curvature-related spin orbit coupling’ in C 60 plays a dominant role in the obtained spin-related phenomena. The measured magneto-photocurrent and magneto-electroluminescence responses in C 60 diodes are dominated by the difference in the g -values of hole and electron polarons in the fullerene molecules. We also obtained giant magneto-resistance of ∼10% at 10 K in C 60 spin-valve devices, where spin polarized holes are injected into the C 60 interlayer. In addition, using the technique of spin-pumping in NiFe/C 60 /Pt trilayer devices with various C 60 interlayer thicknesses we determined the spin diffusion length in C 60 films to be 13 ± 2 nm at room temperature.
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Introduction of a (Ph 3 P) 2 Pt group into the rim of an open-cage fullerene by breaking a carbon–carbon bond
Treatment of an open-cage fullerene, designated as MMK-9, with (Ph 3 P) 4 Pt in toluene solution at room temperature allows a (PPh 3 ) 2 Pt unit to be incorporated into the rim of the cage so that it becomes an integral part of the carbon cage skeleton. The structure of the adduct has been determined by single crystal X-ray diffraction and reveals that the platinum atom has planar PtC 2 P 2 coordination, rather than the usual η 2 -bonding to an intact C–C double bond of the fullerene.
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- Award ID(s):
- 1807637
- PAR ID:
- 10431804
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 57
- Issue:
- 79
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 10218 to 10221
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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