  Ferrogels and magnetic elastomers differentiate themselves from other
materials by their unique capability of reversibly changing shape and
mechanical properties under the influence of an external magnetic field. A
crucial issue in the study of these outstanding materials is the interaction
between the mesoscopic magnetic particles and the polymer matrix in which they
are embedded. Here we analyze interactions between two such particles connected
by a polymer chain, a situation representative for particle-crosslinked
magnetic gels. To make a first step towards a scale-bridging description of the
materials, effective potentials for mesoscopic configurational changes are
specified using microscopic input obtained from simulations. Furthermore, the
impact of the presence of magnetic interactions on the probability
distributions and thermodynamic quantities of the system is considered. The
resulting mesoscopic model potentials can be used to economically model the
system on the particle length scales. This first coarse-graining step is
important to realize simplified but realistic scale-bridging models for these
promising materials.

Soft Condensed Matter;Statistical Mechanics