Institut Laue-Langevin

New method for simulation of complex fluids

A new method has allowed realistic simulation of complex fluids for the first time. With the "coarse graining" method, physicists from Forschungszentrum Jülich, the University of Vienna, the University of Rome, and the ILL used spheres (on the right) to replace the complex macromolecules of the mixture of star polymers (yellow and blue) and linear polymers (red) shown on the left. They integrated the eliminated information as averages into the simplified system so that the characteristics of the substances were retained.

Photos: Forschungszentrum Jülich/University of Vienna

Elaborated small angle neutron scattering experiments at the instrument D11, using contrast variation, proved that the interactions between the spheres of the coarse-grained model realistically simulate the conditions in the real system.

The physicists are especially proud of the excellent agreement between theoretical predictions and experimental results. The method will now open up a spectrum of possibilities for studying the physical properties of a whole range of different complex mixtures.

A publication in Physical Review Letters on 3 June 2011.