2013, Leitner, T., Buchner, F., Luebcke, A., Rouzée, A., Rading, L., Johnsson, P., Odelius, M., Karlsson, H.O., Vrakking, M., Wernet, P.

Time and energy resolved photoelectron distributions of photo-excited Nal are presented. A splitting in the photo-excited state suggested by calculations of the intramolecular potential energy surfaces could be confirmed experimentally for the first time.

2014, Boll, R., Rouzée, A., Adolph, M., Anielski, D., Aquila, A., Bari, S., Bomme, C., Bostedt, C., Bozek, J.D., Chapman, H.N., Christensen, L., Coffee, R., Coppola, N., De, S., Decleva, P., Epp, S.W., Erk, B., Filsinger, F., Foucar, L., Gorkhover, T., Gumprecht, L., Hömke, A., Holmegaard, L., Johnsson, P., Kienitz, J.S., Kierspel, T., Krasniqi, F., Kühnel, K.-U., Maurer, J., Messerschmidt, M., Moshammer, R., Müller, N.L.M., Rudek, B., Savelyev, E., Schlichting, I., Schmidt, C., Scholz, F., Schorb, S., Schulz, J., Seltmann, J., Stener, M., Stern, S., Techert, S., Thøgersen, J., Trippel, S., Viefhaus, J., Vrakking, M., Stapelfeldt, H., Küpper, J., Ullrich, J., Rudenko, A., Rolles, D.

This paper gives an account of our progress towards performing femtosecond time-resolved photoelectron diffraction on gas-phase molecules in a pump-probe setup combining optical lasers and an X-ray free-electron laser. We present results of two experiments aimed at measuring photoelectron angular distributions of laser-aligned 1-ethynyl-4-fluorobenzene (C8H5F) and dissociating, laser-aligned 1,4-dibromobenzene (C6H4Br2) molecules and discuss them in the larger context of photoelectron diffraction on gas-phase molecules. We also show how the strong nanosecond laser pulse used for adiabatically laser-aligning the molecules influences the measured electron and ion spectra and angular distributions, and discuss how this may affect the outcome of future time-resolved photoelectron diffraction experiments.