TY  - JOUR
AU  - Wang, Jingbo
AU  - de Jeu, Wim H.
AU  - Ziener, Ulrich
AU  - Polinskaya, Marina S.
AU  - Ponomarenko, Sergei A.
AU  - Ruderer, Matthias A.
AU  - Herzig, Eva M.
AU  - Müller-Buschbaum, Peter
AU  - Moeller, Martin
AU  - Mourran, Ahmed
AU  - Rücker, Ulrich
TI  - Monolayer Properties of Asymmetrically Substituted Sexithiophene
JO  - Langmuir
VL  - 30
IS  - 10
SN  - 1520-5827
CY  - Washington, DC
PB  - ACS Publ.
M1  - FZJ-2014-07208
SP  - 2752 - 2760
PY  - 2014
AB  - We present a structural comparison of monolayers on a SiO2 substrate of two asymmetrically substituted sexithiophenes (6T). Molecule 1 consists of 6T with a branched alkyl chain at one end only and shows a crystalline structure. In molecule 2, the bifunctional 6T has in addition at the other end a linear alkyl chain. It displays thermotropic liquid crystalline (LC) behavior. Both compounds form readily single molecular layers from solution. Remarkably, full monolayer coverage can be achieved before multilayer growth starts. LC properties promote preordering near the interface as well as exchange of molecules between the growing domains, thus regulating the domain sizes. As a result, the LC compound 2 forms single-molecule islands with larger domain sizes compared to compound 1. Surface X-ray investigations indicate that the 6T cores are tilted relative to the layer normal. The tilt angle is as large as 54° for compound 2 compared to 28° for compound 1. For molecule 2, interfacial constraints and packing requirements because of the asymmetric substitution cause a rather loosely organized core structure.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000333235500020
DO  - DOI:10.1021/la404918b
UR  - https://juser.fz-juelich.de/record/185828
ER  -