102 Cardwell Hall
Gas phase molecules can be aligned – their bonds can be forced into particular directions in space – using intense, ultrashort laser pulses. The molecules are polarized by the electric field of the light and line up with it. Since pioneering work by several groups around the turn of the century, this technique has been widely used to study ground-state molecules in the frame of reference of their own bonds, the so-called molecular frame. I will discuss recent work in our group that extends these measurements to highly differential quantities like molecular-frame photoelectron angular distributions. But the molecular frame picture can break down, particularly in excited states of molecules, if rotational motion of the molecule is not slow compared to electronic motion within it. I will discuss how molecular alignment might provide us with a detailed view of light-driven molecular dynamics in this situation too.