LAUSR

The structure and morphology of organic thin films on solid substrates influence their functional properties. Therefore, knowledge of molecular structure, orientation, diffusion, and involved interactions on particular surfaces is required to gain control over the growth process and prepare layers with the required functionality. However, the resulting morphology is dictated by the delicate interplay of several interactions, which in many cases results in novel and unexpected behavior. Here, we show that strong interaction of 4,4′-biphenyl dicarboxylic acid (BDA) with the step edges on Cu(001) results in the formation of densely packed molecular row, which causes the step edge passivation. The step edge passivation limits the BDA diffusion over the step edges and inhibits the attachment of additional BDA molecules preventing nucleation and growth of molecular islands on the step edges. Our results thus provide fundamental insight into the anomalous growth behavior exhibited by certain organic/inorganic sy...