TY  - JOUR
AU  - Busiakiewicz, A.
AU  - Karthäuser, S.
AU  - Homberger, M.
AU  - Kowalzik, P.
AU  - Waser, R.
AU  - Simon, U.
TI  - Electronic transport properties of individual 4,4'-bis(mercaptoalkyl)-biphenyl derivatives measured in STM-based break junctions
JO  - Physical Chemistry Chemical Physics
VL  - 12
SN  - 1463-9076
CY  - Cambridge
PB  - RSC Publ.
M1  - PreJuSER-11169
SP  - 10518 - 10524
PY  - 2010
N1  - The authors thank Birgit Hahn and Brigitte Hermanns (both IAC) for the support in the preparation of the acetyl protected MABPs. Financial support by the German Research Foundation (DFG) and the Institute Functional Molecular Systems for Information Technology (IFMIT) is gratefully acknowledged.
AB  - Electronic transport measurements of single, systematically varied 4,4'-bis(mercaptoalkyl)-biphenyl derivatives (MABP) are performed in a controlled test-device. The molecules are composed of a central biphenyl unit (BP) carrying two mercaptoalkyl substituents with different chain lengths (m, n = number of CH(2)-units), in the para-position of the BP unit. The total length of both spacers is m + n = 10. The molecular conductance of these individual MABPs deposited on Au (111) substrates is studied using STM-based break junctions. It is shown that the molecular conductance depends on the relative position of the BP unit within the molecule. In the case of the symmetric derivative 5BP5 a value of 0.07 +/- 0.01 nS is obtained, while for 1BP9 the molecular conductance is doubled and a value of 0.17 +/- 0.03 nS results. This relatively high value of conductance for the single Au(tip)-1BP9-Au(substrate) junction is attributed to an increased coupling of the BP unit to the adjacent electrode, i.e. the STM-tip or the Au-substrate. We address the role of the specific contact situation (-S-Au) and of the position of the electrically active molecular moiety and thus come to a deeper understanding of the electronic transport properties of 4,4'-bis(mercaptoalkyl)biphenyl derivatives.
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:20607163
UR  - <Go to ISI:>//WOS:000281352300047
DO  - DOI:10.1039/c004245e
UR  - https://juser.fz-juelich.de/record/11169
ER  -