SEMINÁRIOS DO DEPARTAMENTO DE FÍSICA APLICADA

Data: 07/04/2022 (5a.Feira)

Horário: 14h

Local: Auditório do IFGW

Palestrante:  Prof. Dr. Shadi Fatayer

Applied Physics, Division of Physical Science and Engineering, KAUST, Thuwal, Saudi Arabia.

Título: "Determination and control of charge states of individual molecules by AFM”

Abstract:

The physicochemical properties of molecules adsorbed on surfaces are charge-state dependent. Insulating films serve as an ideal platform to study the physics and chemistry of charged molecules, because these films avoid charge leakage. However, investigating individual charged molecules on insulators is experimentally challenging. The atomic force microscope (AFM), capable of single-electron sensitivity and atomic resolution, is suitable to be used with insulators. I will first show how the charge state of molecules can be controlled. Then, I will present how different aspects of charged molecules can be accessed with the AFM: (i) How using the AFM as a single-electron current meter allows for tunneling spectroscopy to be performed on insulators and electron-transfer properties probed, (ii) how reversible chemical reactions can be induced by charging molecules and (iii) the insights gained via resolving the atomic structure of individual molecules in different charge states.