Current (I)-Voltage (V) characteristics of the self-assembled monolayer (SAM) of π-conjugated, 4,4'-1,4-phenylenebis(methylidynenitrilo)bisbenzene thiolate (PMNBT) adsorbed on Au (111) substrate have been investigated by scanning tunneling microscopy (STM). The measured tunneling current in the case of PMNBT SAM is much higher than that in the case of dodecanemonothiolate (DDMT) molecules. Furthermore, the PMNBT SAMs appear to exhibit a pronounced rectification of the tunneling current not observed in the case of DDMT. Possible reasons for the difference between the I-V characteristics of the two molecules are identified.
Nanotechnology, 2005. 5th IEEE Conference on; 08/2005