# Univ.-Prof. Dr. Christoph Dellago

Faculty of Physics

University of Vienna

Sensengasse 8/9

1090 Wien, Austria

E: christoph.dellago@univie.ac.at

T: +43-1-4277-51260

F: +43-1-4277-9732

**Administrative Assistant:**

Dr. Claudia Rennhofer

E: claudia.rennhofer@univie.ac.at

T: +43-1-4277-51261

F: +43-1-4277-9732

Prof. Dellago's research interests span a diverse set of topics in computational statistical mechanics and molecular simulation ranging from the chaotic dynamics of classical many-particle systems to chemical reactions and the behavior of nanoscale matter.

Early in his career, Dellago, together with Harald Posch at the University of Vienna, studied the Lyapunov instability characterizing the exponentially fast separation of initially close atomic trajectories in liquids and solids. Dellago succeeded in developing efficient computer simulation algorithms that permitted the calculation of full Lyapunov spectra for hard sphere systems and used them to study the properties of multifractal phase space distributions of dissipative non-equilibrium systems and the relation between Lyapunov instability and transport.

After graduation Dellago used a Schrödinger fellowship of the Austrian Science Fund to join the research group of David Chandler at UC Berkeley. There, he was inspired to think about the problem of rare events simulation. Dellago contributed to the development of transition path sampling (TPS), a computer simulation technique based on a statistical mechanics of trajectories. The high efficiency of transition path sampling has opened many new possibilities, ranging from the nucleation of phase transitions to chemical reactions in solution and protein folding. Today, Dellago continues to advance the transition path sampling methodology. Recent work includes the application of Jarzynski's theorem to the calculation of reaction rate constants, the calculation of activation energies in systems with unknown reaction coordinate, the biased sampling of fast switching trajectories, and the sampling of long diffusive trajectories.

After taking up a faculty position first at the University of Rochester and then as a full professor at the University of Vienna, Dellago has widened his research interests. Together with his group members and Dr. Gerhard Hummer from the NIH, he has studied proton transport through small pores finding that protons interact Coulombically with defects in water chains. In other work, Dellago has used ab initio simulations to study the hydration dynamics of Calcium ions in liquid water and the dissociation of hydrochloric acid in liquid glycerol. Another new focus of Dellago's research is the structure and dynamics of nanocrystalline matter and of colloidal crystals.

In 2005 Prof. Dellago received the Raymond and Beverly Sackler Prize in the Physical Sciences administered by Tel-Aviv University for his contributions to the dynamics and thermodynamics of complex molecular systems.