We have prepared pentacene films on Si, A12O3, and glass substrates by thermal evaporation and have investigated their optical properties at room temperature over a wide range of frequencies from infrared to ultraviolet (5 meV to 6.5 eV). A series of optical phonon modes and electronic transitions have been observed. The internal vibrational modes in the infrared region match well their molecular counterparts but the electronic transitions show substantial changes from those of a free pentacene molecule. The HOMO-LUMO gap energy of the pentacene films deposited on A12O3 and glass substrates is 1.85 eV.
|Number of pages||4|
|Journal||Journal of Superconductivity and Novel Magnetism|
|Publication status||Published - 2002|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics