Two-dimensional self-assemblies of azobenzene derivatives: effects of methyl substitution of azobenzene core and alkyl chain length.

Elucidating the correlation between the molecular arrangement and physical properties of organic compounds is critical to facilitating the development of advanced functional materials. X-ray structural analyses are generally performed to clarify this relationship. Several attempts have been made to ascertain the links between three-dimensional (3D) crystals and their two-dimensional (2D) structures, which can be revealed by scanning tunnelling microscopy (STM) at the molecular level.

Halogen bond-directed self-assembly in bicomponent blends at the solid/liquid interface: effect of the alkyl chain substitution position.

The fabrication of well-organised molecular assemblies on surfaces is fundamental for the creation of functional molecular systems applicable to nanoelectronic and molecular devices. In this study, we investigated the effect of substitution positions of alkyl chains on the formation of halogen-bonded molecular networks. For this purpose, building blocks with different head groups (, pyridine (Py) or tetrafluoro-iodobenzene (FI)) were substituted with hexadecyloxy chains at either the 3,4- or the 3,5-positions.

Well-organised two-dimensional self-assembly controlled by formation of a Cu(II)-coordinated rufigallol derivative: a scanning tunnelling microscopy study.

The two-dimensional self-assembly of rufigallol derivatives and their metal coordination were studied by scanning tunnelling microscopy. Cu(II)-coordinated rufigallol derivatives exhibited columnar structures with some defects, whereas regular and linear structures were formed upon metal coordination at solid/liquid interfaces.

Dynamic host-guest behavior in halogen-bonded two-dimensional molecular networks investigated by scanning tunneling microscopy at the solid/liquid interface.

The fabrication of supramolecularly engineered two-dimensional (2D) networks using simple molecular building blocks is an effective means for studying host-guest chemistry at surfaces toward the potential application of such systems in nanoelectronics and molecular devices. In this study, halogen-bonded molecular networks were constructed by the combination of linear halogen-bond donor and acceptor ligands, and their 2D structures at the highly oriented pyrolytic graphite/1-phenyloctane interface were studied by scanning tunneling microscopy. The bi-component blend of the molecular building blocks possessing tetradecyloxy chains formed a lozenge structure halogen bonding.

Coordination-Driven Construction of Porphyrin Nanoribbons at a Highly Oriented Pyrolytic Graphite (HOPG)/Liquid Interface.

Nanostructures were built at the solid/liquid interface by self-assembly and/or coordination bonds. Metalloporphyrins bearing two external coordination sites and long alkyl chains allowed the self-assembly of the compounds on highly oriented pyrolitic graphite. After addition of a metal ion, long transition-metal linked porphyrin nanoribbons were obtained and visualized by scanning tunneling microscopy.

Hexagonal array formation by intermolecular halogen bonding using a binary blend of linear building blocks: STM study.

Hexagonal arrays were fabricated via intermolecular halogen bonding between two linear molecular building blocks in a bicomponent blend. The substitution position of the pyridine N atom involved in the halogen bond plays an important role in the formation of the hexagonal structures.