Potential energy surfaces and the associated reaction paths they define have played an important role in understanding the assembly of molecules. In this talk I will show that similar mechanistic effects exist in light-driven self-organization of metal nanoparticles; by analogy, atoms are replaced by silver nanoparticles and optical trapping/optical binding interactions serve as “covalent bonds”.

One of the most fundamental issues in water science is the characterization of H-bonding configuration formed on surfaces and H-atom transfer through hydrogen bonds. Ideally, attacking this problem requires the access to the internal degrees of freedom of water molecules, i.e. the directionality of OH bonds. In this talk, I will demonstrate the possibility of discerning the O-H directionality in real space through submolecular-resolution orbital imaging of interfacial water, using a cryogenic scanning tunneling microscope (STM) [1].

The ability to control and manipulate small objects is essential in studying many microscopic phenomena, from colloidal physics to molecular biology, and more recently, nanophotonics. Optical tweezers offer a unique non-contact approach to control the position and orientation of microscopic particles. In this lecture, I will introduce the development of optical tweezers with emphasis on the underlying physics of optical trapping, especially the interactions of light with plasmonic nanoparticles.

In the first part, I will present our recent work on tunneling electron-induced tautomerisation of
single porphycene molecules on a Cu(110) surface [1,2]. In particular, how this tautomerisation can
be controlled by nearby atoms or molocules will be discussed.

Using sunlight to facilitate and promote valuable chemical reactions is an ideal solution to the challenge of meeting future energy demands.  Our group aims to address fundamental questions concerning surface plasmon resonance (SPR)-mediated interfacial electron transfer (ET) and photothermal heating in order to develop new materials and strategies for efficiently converting solar energy to chemical energy.  In this talk, I will show how we unambiguously reveal the mechanics of plasmon-mediated electron transfer (PMET) in Au/TiO₂ heterostructures under visible light (&l