Absorption and fluorescence spectra of C60 fullerene concentrated solutions in hexane and polystyrene at 77–300 K
| Autor: | V. S. Pavlovich, E. M. Shpilevsky |
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| Rok vydání: | 2010 |
| Předmět: | |
| Zdroj: | Journal of Applied Spectroscopy. 77:335-342 |
| ISSN: | 1573-8647 0021-9037 |
| Popis: | The locations of the $$ 0_0^0 $$ -bands for S1← S0 and S1 → S0 transitions have been found for C60 solutions in hexane. It is shown that the profile of the S1 ← S0 band is mainly shaped by hu(4), t1u(4)- and hg(1), ag(2)- modes that are active in absorption. Bands involving the hu(4)- and t1u(4)-modes in the emission process have also been identified in the fluorescence spectrum. The appearance of the $$ 0_0^0 $$ -band in the forbidden 11T1g ← 11Ag transition is explained by symmetry reduction in the C60+environment system due to the interaction of electrons with local phonons. The temperature coefficients of the red shift for the 256.3- and 328.3-nm bands of allowed 1T1u ← 11Ag transitions for C60 in hexane are equal to –1.45 and –0.46 cm–1·K–1, respectively. The peak and half-width values of the 337.2-nm band for C60 in polystyrene remain unchanged on cooling to 77 K. Absorption in the 700–800-nm region for concentrated hexane solutions of fullerene at 292 K results from the production of (C60)n-clusters. |
| Databáze: | OpenAIRE |
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