Triplet states of C[sub 60] and C[sub 70] in solution: Long intrinsic lifetimes and energy pooling

Journal Article · Thu Oct 28 04:00:00 EDT 1993 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100145a002· OSTI ID:5576583

Fraelich, M R; Weisman, R B ^[1]

---

1. Rice Univ., Houston, TX (United States)

Lifetimes of the lowest triplet electronic states of C[sub 60] and C[sub 70] have been measured in room temperature benzene solution. With bimolecular quenching suppressed, the exponential lifetimes are found to be 133 [mu]s for C[sub 60] and > 2.2 ms for C[sub 70]. Triplet C[sub 60] and C[sub 70] are self-quenched with rate constants of 1.5 [times] 10[sup 7] and 8.5 [times] 10[sup 7] M[sup [minus]1] s[sup [minus]1], respectively. In mixed solutions of C[sub 60] and C[sub 70], triplet electronic excitation is efficiently and reversibly transferred at approximately 20% of the diffusion-limited rate. From the ratio of forward and reverse energy transfer rate constants, the T[sub 1]-S[sub 0] gap of C[sub 60] is deduced to be 102 [plus minus] 30 cm[sup [minus]1] greater than that of C[sub 70]. The long intrinsic lifetimes and rapid energy pooling suggest that improved efficiencies may be possible for many applications of fullerene photochemistry and photophysics. 24 refs., 3 figs., 1 tab.

• OSTI ID: 5576583
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 97:43; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360606 -- Other Materials-- Physical Properties-- (1992-)
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
AROMATICS
BENZENE
CARBON
CHEMISTRY
DIFFUSION
DISPERSIONS
ELEMENTS
ENERGY LEVELS
ENERGY TRANSFER
EXCITED STATES
FULLERENES
HYDROCARBONS
LIFETIME
MIXTURES
MULTIPLETS
NONMETALS
ORGANIC COMPOUNDS
PHOTOCHEMISTRY
SOLUTIONS
TRIPLETS