Designing of a “Perfect” Porphyrin Molecule for the Mechanically Controllable Break Junction Experiments

The biggest challenge of molecular electronics is to condense the functionality of an electronic device into a single molecule and to exploit the functional versatility offered by the chemical diversity of molecules for electronic device purposes.<br/>Porphyrins and their related macrocycles are promising building blocks for the construction of bio-inspired molecular devices. Nature itself offers magnificent examples of porphyrin's usefulness, such as activating and transporting molecular oxygen in mammals and harnessing sunlight in plant photosynthetic systems.<br/>In spite of their potential, obtaining well-defined single-molecule conductance features is a difficult task. Due to π-stacking porphyrins can form a variety of junction configurations, leading to a large spread in conductance values using the mechanically controllable break junctions (MCBJ) technique. This limits further progress in investigating the molecular functionalities on a single molecule level in porphyrin molecules.<br/>In this presentation, I will show that by close interaction between synthetic chemists and physicists a “perfect” porphyrin molecular design for mechanically controllable break junctions can be achieved, leading to well-defined, highly conducting molecular junctions. This opens further prospects for “porphyronics” – porphyrin-based molecular electronics.