10.1021/jacs.6b06877.s003
Yuji Yamaguchi
Yuji
Yamaguchi
Maki Takubo
Maki
Takubo
Keisuke Ogawa
Keisuke
Ogawa
Ken-ichi Nakayama
Ken-ichi
Nakayama
Tomoyuki Koganezawa
Tomoyuki
Koganezawa
Hiroshi Katagiri
Hiroshi
Katagiri
Terazulene
Isomers: Polarity Change of OFETs through
Molecular Orbital Distribution Contrast
American Chemical Society
2016
Molecular Orbital Distribution Contrast Intermolecular
π- conjugation system
LUMO
HOMO
terazulene
n-type transistor behavior
FET
TAz 4 exhibits
TAz 3 exhibit ambipolar characteristics
OFET
TAz 2
azulene unit
TAz 4
2016-08-11 00:00:00
Dataset
https://acs.figshare.com/articles/dataset/Terazulene_Isomers_Polarity_Change_of_OFETs_through_Molecular_Orbital_Distribution_Contrast/3776550
Intermolecular orbital
coupling is fundamentally important to organic
semiconductor performance. Recently, we reported that 2,6′:2′,6″-terazulene
(<b>TAz1</b>) exhibited excellent performance as an n-type organic
field-effect transistor (OFET) via molecular orbital distribution
control. To validate and develop this concept, here we present three
other terazulene regioisomers, which have three azulene molecules
connected at the 2- or 6-position along the long axis of the azulene,
thus constructing a linear expanded π-conjugation system: 2,2′:6′,2″-terazulene
(<b>TAz2</b>), 2,2′:6′,6″-terazulene (<b>TAz3</b>), and 6,2′:6′,6″-terazulene (<b>TAz4</b>). <b>TAz2</b> and <b>TAz3</b> exhibit ambipolar
characteristics; <b>TAz4</b> exhibits clear n-type transistor
behavior as an OFET. The lowest unoccupied molecular orbitals (LUMOs)
of all terazulenes are fully delocalized over the entire molecule.
In contrast, the highest occupied molecular orbitals (HOMOs) of <b>TAz2</b> and <b>TAz3</b> are delocalized over the 2,2′-biazulene
units; the HOMOs of <b>TAz4</b> are localized at one end of
the azulene unit. These findings confirm that terazulene isomers which
are simple hydrocarbon compounds are versatile materials with a tunable-polarity
FET characteristic that depends on the direction of the azulene unit
and the related contrast of the molecular orbital distribution in
the terazulene backbone.