Molecular Chains: Arranging and Programming Logic Gates

Abstract

One particularly fascinating vision for charge-operated devices is the controlled assembly of structures from single surface-deposited molecules. Here, we report on the assembly of linear clusters that consist of phthalocyanine (H2Pc) molecules on a Ag(111) surface. The molecules are imaged as well as manipulated with a low-temperature scanning tunneling microscope (STM). Upon deprotonation of every second H2Pc, the resulting HPc molecule exhibits an isomeric bistability which can be used as inputs in logic gates. Combining our STM measurements with density functional theory calculations we show that the HPc isomers exhibit a repulsive electrostatic interaction with adjacent H2Pc molecules which, due to the asymmetric charge distribution on HPc, results in a counterclockwise or clockwise molecule tilt of the latter, thereby defining the logic 0 and 1 of the output. It is shown that information can be relayed along molecule chains over distances equivalent to at least nine molecules.

Growth of 1D ClAlPc molecular chains mediated by graphene moiré patterns

“…This has allowed the observation of one-dimensional systems, developed from molecular units as building blocks, with very exciting properties such as Yu-Shiba-Rusinov bound states, 1 topological phases, 2 or enhanced single-molecule superradiance. 3 From the application point of view, important achievements, such as the observation of high conductivity in doped polyacetylene, 4 charge distribution control, 5 and the development of prototypes of molecule-based logic gates, 6,7 among others, have been accomplished in 1D organic systems. Tailoring such low dimensional architectures was possible by engineering STM tip-assisted manipulation of individual molecules, edge-templated assembly, or diverse on-surface synthesis strategies that rely on predefined chemical precursor species.…”

“…Tailoring such low dimensional architectures was possible by engineering STM tip-assisted manipulation of individual molecules, edge-templated assembly, or diverse on-surface synthesis strategies that rely on predefined chemical precursor species. [1][2][3][5][6][7][8][9] The growth of 1D supramolecular structures driven mainly by dispersive intermolecular forces is much more challenging than when it is predominantly governed by other non-covalent interactions such as hydrogen bonding or metal-ligand bonding, which are stronger and more directional. In general, the formation of on-surface molecular architectures via dispersive interactions is ruled by a subtle interplay between molecule-molecule and molecule-substrate interactions, in which the local polarizability of the supporting surface plays a major role.…”

Strain-Enhanced Formation of Delocalized Exciton States in Phthalocyanine Crystalline Thin Films

“…Organic semiconductors are well-known candidates for flexible, wearable, and portable novel electronic and photonic devices − because of their tunable optoelectronic properties, versatile synthetic pathways, and desirable mechanical properties. , More recently, the advent of new thin-film fabrication techniques − in conjunction with sustained efforts to gain more insight into the structure–property relationships of these materials stimulated an increasing number of researchers to explore small-molecule semiconductors as possible platforms for robust coherent excitonic states, − topological states, − and quantum applications. , …”

Principles of Molecular Machines at the Single-Molecule Scale

“…These molecular motors can be further integrated into molecular cars and potentially carry out specific missions at the atomic scale, such as drug delivery . Logic gates and single-molecule transistors are demonstrated to be plausible with molecular shuttles, indicating their potential applications in on-chip integrated circuits. , In the field of biosynthesis, artificial molecular machines have been developed for sequence-specific oligomer synthesis. − Switching of product chirality , and stereodivergent synthesis can also be achieved with molecular machines. The huge application potential of the molecular machine in the fields of molecular electronics, catalysis, sensor, and so on is also demonstrated, exhibiting the importance of molecular machines to the future world. ,,− …”

“…13 Logic gates and single-molecule transistors are demonstrated to be plausible with molecular shuttles, indicating their potential applications in on-chip integrated circuits. 14,15 In the field of biosynthesis, artificial molecular machines have been developed for sequence-specific oligomer synthesis. 16−18 Switching of product chirality 19,20 and stereodivergent synthesis 21 can also be achieved with molecular machines.…”