Berlin 2008 – wissenschaftliches Programm

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CPP: Fachverband Chemische Physik und Polymerphysik

CPP 3: Liquid Crystals and Polar Fluids

CPP 3.9: Vortrag

Montag, 25. Februar 2008, 12:15–12:30, C 264

The impact of substrate-induced molecular orientation on dimerization in nanoreactors — •Randy Mathes and Martin Schoen — Stranski-Laboratorium, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin

We investigate the impact of substrate-induced molecular orientation on dimerization in nano-confinement. Equilibrium properties are examined for different substrates and bond lengths and are compared to a bulk system. The system under study is a reacting mixture of Lennard-Jones spheres and homonuclear Lennard-Jones diatomics. We use Gibbs ensemble Monte Carlo to examine the bulk phase diagram. Substrate and bond length effects in confinement are studied using grand canonical Monte Carlo. In bulk systems we generally find higher mole fractions of dimers at higher densities and lower temperatures. As expected we find higher mole fractions of dimers in non-orientating confinement compared to a bulk system at fixed chemical potential. We exploit the preferred in-plane orientation of dimers near walls to tune dimer rates in confinement by enforcing molecular orientation perpendicular to the walls. From adsorption calculations we also expect a strong dependence on bond length.