Low level optical absorption measurements on organic semiconductors

Autor:	Jordi Andreu, Marco Stella, M. Fonrodona, Fredy Rojas, José Miguel Asensi, Joan Bertomeu, Joaquim Puigdollers, Cristobal Voz, J. Escarré
Rok vydání:	2006
Předmět:	Fullerene Photothermal spectroscopy Absorption spectroscopy Chemistry Analytical chemistry Condensed Matter Physics Spectral line Electronic Optical and Magnetic Materials Ion Organic semiconductor Pentacene chemistry.chemical_compound Materials Chemistry Ceramics and Composites Spectroscopy
Zdroj:	Journal of Non-Crystalline Solids. 352:1663-1667
ISSN:	0022-3093
Popis:	The optical absorption of n-type (C 60 and PTCDA) and p-type (CuPc and pentacene) organic semiconductors is investigated by optical transmission and photothermal deflection spectroscopy. The usual absorption bands related to HOMO-LUMO transitions are observed in the high absorption region of transmission spectra. Photothermal deflection spectroscopy also evidences exponential absorption shoulders with characteristic energies 47 meV for CuPc, 38 meV for pentacene, 50 meV for PTCDA and 87 meV for C 60 . In addition, broad bands in the low absorption level are observed for C 60 and PTCDA. These bands have been attributed to contamination due to air exposure. On the other hand, in CuPc a clear absorption peak at 1.12 eV is observed with smaller features at 1.04 eV, 1.20 eV and 1.33 eV. These peaks are attributed to transitions between the Pc levels of CuPc ions. Finally, the optical absorption expected in blends of organic semiconductors is estimated by an effective media approximation.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::2729a2a6dc7ae34d84549daf17fb2d26 https://doi.org/10.1016/j.jnoncrysol.2005.09.048 Zobrazit plný text záznamu Full Text from ScienceDirect