The R-matrix method for attosecond spectroscopy

Summary form only given. The advent of new XUV light sources such as free electron lasers, and the development of high harmonic emission both as a light source and as a direct probe, coupled with advances in detector technology and the laser alignment of molecules, has opened up the possibility of observation, initiation and control of the fastest molecular processes. Exposing aligned molecules to these short, femtosecond to sub-femtosecond pulses leads to ionisation, and the angular distribution of ejected electrons encodes information about the parent molecule [1,2]. High harmonic emission from molecules can also encode information about molecular structure and dynamics [3,4].