Selective Attachment of 1,4-Benzenedimethanethiol on the Copper Mediated Si(111)−(7 × 7) Surface through S−Cu Linkage.

The well-defined and patterned copper clusters formed on the Si(111)−(7 × 7) surface have been employed as a template for selective binding of 1,4-benzenedimethanethiol (HS−CH2−C6H4−CH2−SH, 1,4-BDMT), to form ordered molecular nanostructures. Scanning tunneling microscopic (STM) studies showed that each 1,4-BDMT molecule preferentially binds to two neighboring copper atoms within one copper cluster through the S−Cu interaction with its molecular plane parallel to the surface, whereas some 1,4-BDMT bond to individually adsorbed copper atoms, resulting in an upright configuration. Large-scale two-dimensional molecular nanostructures can be obtained using this patterned assembly technique. Our experiments demonstrate the feasibility for controllable growth of ordered molecular nanostructures on the Si(111)−(7 × 7) surface. [ABSTRACT FROM AUTHOR]