Simulation of the chemical storage of data via metal-ligand chelation

The 8-hydroxyquinoline forms metal–ligand chelating complexes with almost all metals, with various bonding energies and geometries, and at different pHʹs. As several studies have demonstrated the manipulation of atoms on the surface via scanning probe microscopies, it seems that (8-hydroxyquinoline)–metal ion monodentate complexes, which are also stable and tunable by external conditions, e.g. pH, would be good candidates for devices that will store data via spatially-addressable, Angstrom-level placement of atoms. This contribution uses semi-empirical calculations to investigate the possibility of using pairs of quasi-identical metallic atoms, e.g. Zn–Cu and Pd–Cd, disposed in a simple cubic lattice, and atomic force microscopy tips functionalized with 8-hydroxyquinoline to read with Angstrom-level resolution the information encoded in the probed surface through the placement of single `informationʹ atoms.