  Clusters of spherical particles with isotropic attraction favour compact
structures that maximise the number of energetically optimal nearest-neighbour
interactions. In contrast, dipolar interactions lead to the formation of chains
with a low coordination number. When both isotropic and dipolar interactions
are present, the competition between them can lead to intricate knot, link and
coil structures. Here, we investigate how these structures may self-organise
and interconvert in clusters bound by the Stockmayer potential (Lennard-Jones
plus point dipole). We map out the low-lying region of the energy landscape
using disconnectivity graphs to follow how it evolves as the strength of the
dipolar interactions increases. From comprehensive surveys of isomerisation
pathways, we identify a number of rearrangement mechanisms that allow the
topology of chain-like structures to interconvert.
