Observation and control of ultrafast surface photochemistry

The ultimate goal of any branch of Chemistry, including surface Chemistry, is to understand reactions at a fundamental level. In order to achieve this, it is necessary to both observe the reaction on an atomic length scale, and also to monitor the reaction on the same time scale as bond breaking and making - the femtosecond timescale (1 fs = 10-15 s). With the advent of scanning probe microscopy, the observation of surface reactions at the atomic length scale has become almost routine. However, observing the dynamics of surface reactions with femtosecond accuracy still remains a considerable challenge. This proposal will address this issue. It aims to establish the foundations for understanding the detailed dynamics of surface processes, by using state-of-the-art femtosecond pump-probe techniques to monitor reactions in real time. It will also investigate the possibility, long discussed theoretically but not yet achieved experimentally, of using shaped femtosecond laser pulses to control surface photochemistry. If this control technique is successful it will have a huge impact and will contribute greatly to our understanding of surface reaction processes. The programme of research will be made possible by bringing together two independent well-established research groups within the UCL Chemistry department to form a unique team with the necessary experimental expertise in both surface science and ultrafast laser technology.