Alkali-Metal-Intercalated Percolation Network Regulates Self-Assembled Electronic Aromatic Molecules.

In the continuously growing field of correlated electronic molecular crystals, there is significant interest in addressing alkali-metal-intercalated aromatic hydrocarbons, in which the possibility of high-temperature superconductivity emerges. However, searching for superconducting aromatic molecular crystals remains elusive due to their small shielding fraction volume. To exploit this potential, a design principle for percolation networks of technologically important film geometry is indispensable. Here the effect of potassium-intercalation is shown on the percolation network in self-assembled aromatic molecular crystals. It is demonstrated that one-dimensional (1D) dipole pairs, induced by dipole interaction, regulate the conductivity, as well as the electronic and optical transitions, in alkalimetal-intercalated molecular electronic crystals. A solid-solution growth methodology of aromatic molecular films with a broad range of stability is developed to uncover electronic and optical transitions of technological importance. The light-induced electron interactions enhance the charge-carrier itinerancy, leading to a switchable metal-to-insulator transition. This discovery opens a route for the development of aromatic molecular electronic solids and long-term modulation of electronic efficacy in nano-technologically important thin films.