Hannover 2010 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

MO: Fachverband Molekülphysik

MO 18: Cluster I

MO 18.5: Talk

Thursday, March 11, 2010, 11:30–11:45, F 102

Spectroscopy of PTCDA molecules attached to Ar-, Ne- and hydrogen-Clusters formed inside helium nanodroplets — •Markus Müller, Matthieu Dvorak, and Frank Stienkemeier — Physikalisches Institut, Universität Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg

Helium Nanodroplet Isolation (HENDI) spectroscopy has become a well established method for studying atoms, molecules and their complexes. The appealing physical properties of helium droplets such as their low temperature (380mK), the weak interactions with atoms and molecules, and the superfluid property make them a favorite matrix for spectroscopy.

In order to study the phase and structure of argon, hydrogen and neon clusters formed inside helium droplets, we dope them with organic molecules (PTCDA) and probe the vibronic spectrum by means of laser induced fluorescence (LIF). The width and shift as well as the line shape of the transitions observed for different sizes give us information about the interaction between the molecule and the cluster environment. By varying the cluster sizes up to some hundreds of atoms and reversing the droplet doping order, the changes in the LIF spectra can be correlated to structural modifications and phase transitions of the clusters.