Paper SS-ThP4
Exploring Photomechanically Switching Molecules on Semiconductor Surfaces

Thursday, November 12, 2009, 6:00 pm, Room Hall 3

The photomechanical switching behavior of organic molecules changes dramatically when the molecules are placed on a surface. Metal surfaces, for example, often quench or slow photomechanical activity due to strong molecular interaction with continuum electronic degrees of freedom. Semiconductor surfaces are expected to induce very different molecular switching behavior due to the presence of a band gap, potentially resulting in longer excited-state lifetimes and enhanced control of photomechanical properties. We have explored the local structure and self-assembly of photomechanical molecules on the semiconducting GaAs(110) surface using variable temperature scanning tunneling microscopy. We will report on the nanoscale response of azobenzene derivatives on GaAs to optical irradiation in the UV-vis spectral regime.