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Mechanisms of adsorption and organization of organic molecules on metallic surfaces play a significant role in the growth of chemically and electronically tuned, monolayer thin films. Intercommunication between functional groups for individual adsorbates can serve as the primary driving force for monolayer crystallinity as well as electronic structure especially in the limit of weak interaction between the adsorbate and substrate. In this talk we will discuss the submonolayer ordering of a chiral molecule, tartaric acid (C4H6O6), weakly bound to an achiral metal surface, Ag(111), as studied with low temperature scanning tunneling microscopy (STM) and density functional theory (DFT). Molecularly resolved images of enantiomerically pure (R, R)- and (S, S)-tartaric acid domains on Ag(111) will be presented and the role of intermolecular hydrogen bonding in stereospecific domain and superlattice formation will be addressed. Additionally, we will consider chiral domain formation and phase separation from a racemic mixture of tartaric acid enantiomers. Lastly we will present differential conductance mapping of tartaric acid molecular domains that highlight an intrinsic decoupling of molecular film electronic states with respect to the metallic lattice. While the chiral expression which drives the formation of enantiomeric domains does not induce stereospecific conductance, we demonstrate electronic differentiation of submonolayer organic domains from the Ag(111) surface. Density functional theory calculations will be discussed as they relate to both the molecular organization as well as the deconvolution of electronic structure between the molecular film and the metallic substrate. |