Competing Interactions in Surface Reticulation with a Prochiral Dicarbonitrile Linker

The organic and metal-directed assembly of a prochiral carbonitrile (CN) oligophenyl molecule on a smooth noble metal substrate was investigated by combined scanning tunneling microscopy and computational modeling. The molecule is functionalized with two CN groups in <i>meta</i> and <i>para</i> positions of the terminating phenyl rings of the <i>p</i>-terphenyl backbone. Upon deposition on a Ag(111) surface, we observe two different organic supramolecular networks, one of them reflecting a chiroselective assembly. After coevaporating small amounts of Co, a hybrid network comprising both CN–phenyl and metal coordination bond motifs could be observed. Intriguingly, the CN group in the <i>para</i> position is favored for the metal coordination, whereas the <i>meta</i> group remains in a CN–phenyl motif. Computational modeling suggest that the high stability of the <i>meta</i> CN–phenyl motif is causing this selective interaction. An increase of the metal adatom ratio eventually induces divergent assembly of a room-temperature stable 2D random metal–organic network

Hierarchically Organized Bimolecular Ladder Network Exhibiting Guided One-Dimensional Diffusion

The assembly and dynamics of a hierarchical, bimolecular network of sexiphenyl dicarbonitrile and <i>N</i>,<i>N</i>′-diphenyl oxalic amide molecules on the Ag(111) surface are studied by scanning tunneling microscopy at controlled temperature. The network formation is governed by a two-step protocol involving hierarchic interactions, including a novel carbonitrile–oxalic amide bonding motif. For temperatures exceeding ∼70 K, more weakly bound sexiphenyl dicarbonitrile molecules carry out one-dimensional diffusion guided by the more stable substructure of the network held together by the carbonitrile–oxalic amide bonding motif. A theoretical investigation at the <i>ab initio</i> level confirms the different binding energies of the two coupling motifs and rationalizes the network formation and the diffusion pathway

Hierarchically Organized Bimolecular Ladder Network Exhibiting Guided One-Dimensional Diffusion

The assembly and dynamics of a hierarchical, bimolecular network of sexiphenyl dicarbonitrile and <i>N</i>,<i>N</i>′-diphenyl oxalic amide molecules on the Ag(111) surface are studied by scanning tunneling microscopy at controlled temperature. The network formation is governed by a two-step protocol involving hierarchic interactions, including a novel carbonitrile–oxalic amide bonding motif. For temperatures exceeding ∼70 K, more weakly bound sexiphenyl dicarbonitrile molecules carry out one-dimensional diffusion guided by the more stable substructure of the network held together by the carbonitrile–oxalic amide bonding motif. A theoretical investigation at the <i>ab initio</i> level confirms the different binding energies of the two coupling motifs and rationalizes the network formation and the diffusion pathway