TY - JOUR
T1 - Occupied and Unoccupied Levels of Half-Fluorinated and Perfluorinated Rubrene Thin Films Probed by One- And Two-Photon Photoemission
AU - Inoue, Tomoya
AU - Shibuta, Masahiro
AU - Suzuki, Toshiyasu
AU - Nakajima, Atsushi
N1 - Funding Information:
This work was partly supported by Nanotechnology Platform Program (Molecule and Material Synthesis) of the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan (S-19-MS-0041), and was also partly supported by JSPS KAKENHI of Grants-in-Aid for Scientific Research (A) (Grants 15H02002 and 19H00890), of Challenging Research (Pioneering) (Grant 17H06226), and of Grants-in-Aid for Scientific Research (C) (Grant 18K04942). M.S. and A.N. acknowledge financial support by the Deutsche Forschungsgemeinschaft through SFB 1083.
Publisher Copyright:
© 2020 American Chemical Society.
PY - 2020/6/11
Y1 - 2020/6/11
N2 - We measured occupied and unoccupied energy levels of half-fluorinated and perfluorinated rubrenes (C42F14H14, F14-RUB, and C42F28, PF-RUB) thin films prepared on a highly oriented pyrolytic graphite substrate by a combination of one- and two-photon photoemission spectroscopies. It is revealed that the energy levels near the Fermi level (EF) decrease when the fluorination degree increases, where the energies of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) are located at EF - 1.83 eV and EF + 0.9 eV for F14-RUB and EF - 2.51 eV and EF + 0.6 eV for PF-RUB, respectively. The HOMO-LUMO gaps corresponding to the energy for the creation of free photocarriers in molecular films - known as "transport gaps"- are evaluated by 2.7 eV for F14-RUB and 3.1 eV for PF-RUB.
AB - We measured occupied and unoccupied energy levels of half-fluorinated and perfluorinated rubrenes (C42F14H14, F14-RUB, and C42F28, PF-RUB) thin films prepared on a highly oriented pyrolytic graphite substrate by a combination of one- and two-photon photoemission spectroscopies. It is revealed that the energy levels near the Fermi level (EF) decrease when the fluorination degree increases, where the energies of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) are located at EF - 1.83 eV and EF + 0.9 eV for F14-RUB and EF - 2.51 eV and EF + 0.6 eV for PF-RUB, respectively. The HOMO-LUMO gaps corresponding to the energy for the creation of free photocarriers in molecular films - known as "transport gaps"- are evaluated by 2.7 eV for F14-RUB and 3.1 eV for PF-RUB.
UR - http://www.scopus.com/inward/record.url?scp=85086664757&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85086664757&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcc.0c01162
DO - 10.1021/acs.jpcc.0c01162
M3 - Article
AN - SCOPUS:85086664757
SN - 1932-7447
VL - 124
SP - 12409
EP - 12416
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
IS - 23
ER -