Bending Potential as an Important Factor for the Structure of Monomolecular Thiolate Layers on GaAs Substrates

作者：Lu Hao; Terfort Andreas; Zharnikov Michael^*

来源：Journal of Physical Chemistry Letters, 2013, 4(13): 2217-2222.

DOI：10.1021/jz401091y

The presence of a substrate-dependent binding geometry at the anchoring group and its energetics (bending potential) are known to be important in determining the lateral density and structure of self-assembled monolayers (SAMs) of thiolates and selenolates on coinage metal substrates. Here we show that on the technologically important GaAs(001) surface a bending potential exists for thiolate adlayers as well. For this, we used a series of terphenyl-substituted alkanethiols, C6H5(C6H4)(2)(CH2)(n)SH (TPn, n = 0-6), as a suitable model system. The bending potential plays a dominant role in the balance of the structure building interactions in the TPn SAMs on GaAs, resulting in a persistent, %26quot;odd-even%26quot; variation of molecular orientation and packing density in these monolayers as a function of the parity of n. This observation should necessarily be considered for the design of future, functional SAMs on GaAs(001).

• 出版日期2013-7-4