Scanning Tunneling Microscopy for Molecules: Manipulating Electron Transport through the Conduction Gap by Varying the Buffer Layer.

ABSTRACT: In scanning tunneling microscopy of molecules, an insulating buffer layer is often introduced to reduce interactions between adsorbed molecules and the substrate. We demonstrate that the buffer itself strongly influences the wave function of the tunneling electron at the molecule for tunneling through the molecule's electronic transport gap. We use a theory, which provides a very good agreement with prior experiments on platinum phthalocyanine on a NaCl buffer, to study effects of varying the buffer's composition and thickness and show the importance of the buffer's lattice parameter. Expanding the tunneling electron's wave function using molecular orbitals (MOs) additionally shows how to control the relative weights at the highest occupied MO (HOMO), lowest unoccupied MO (LUMO), and energ

SUBMITTER: Grewal A 

PROVIDER: S-EPMC12670310 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature