Magneto-optical studies of photoexcitations in C[sub 61]

Journal Article · Wed Dec 15 04:00:00 EST 1993 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.48.18250· OSTI ID:5660356

Leng, J M; Wei, X; Vardeny, Z V ^[1]; Khemani, K C; Moses, D; Wudl, F ^[2]

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1. Department of Physics, University of Utah, Salt Lake City, Utah 84112 (United States)
2. Institute of Polymers and Organic Solids and Department of Physics Department of Chemistry, University of California, Santa Barbara, California 93106 (United States)

We have used a variety of cw optical and optically detected magnetic-resonance techniques to characterize long-lived photoexcitations in methanofullerene (C[sub 61]) as a dispersion in polystyrene glass, at temperatures below 10 K. We identify triplet excitons with zero-field-splitting (ZFS) parameters [ital D]=105[times]10[sup [minus]4] cm[sup [minus]1] and [ital E]=9[times]10[sup [minus]4] cm[sup [minus]1]. The triplet excitons are characterized by two photoinduced absorption (PA) bands in the triplet manifold at 1.5 and 1.7 eV, both with a lifetime of 160 [mu]sec, and a phosphorescence emission (PL) band with onset at 1.85 eV and a lifetime of 10 [mu]sec. The difference in lifetimes between PA and PL is explained as being due to different recombination kinetics of the triplet sublevels. This and the finite axial symmetry ZFS parameter [ital E][ne]0 compared to [ital E]=0 for triplets in C[sub 60] show the lower symmetry of triplets in C[sub 61], consistent with its postulated distortions from icosahedral symmetry in the ground-state structure.

• DOE Contract Number: FG03-93ER45490
• OSTI ID: 5660356
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 48:24; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360606* -- Other Materials-- Physical Properties-- (1992-)
CARBON
CHEMICAL REACTIONS
COMPOSITE MATERIALS
ELECTRONIC STRUCTURE
ELEMENTS
EXCITONS
FULLERENES
LUMINESCENCE
MAGNETO-OPTICAL EFFECTS
MATERIALS
METHANATION
NONMETALS
ORGANIC COMPOUNDS
ORGANIC POLYMERS
PETROCHEMICALS
PETROLEUM PRODUCTS
PHOSPHORESCENCE
PHOTOLUMINESCENCE
PLASTICS
POLYMERS
POLYOLEFINS
POLYSTYRENE
POLYVINYLS
QUASI PARTICLES
RECOMBINATION
SYNTHETIC MATERIALS
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE
TEMPERATURE RANGE 0000-0013 K