  We study the energy transfer in a classical dipole chain of $N$ interacting
rigid rotating dipoles. The underlying high--dimensional potential energy
landscape is analyzed in particular by determining the equilibrium points and
their stability in the common plane of rotation. Starting from the minimal
energy configuration, the response of the chain to excitation of a single
dipole is investigated. Using both the linearized and the exact Hamiltonian of
the dipole chain, we detect an approximate excitation energy threshold between
a weakly and a strongly nonlinear dynamics. In the weakly nonlinear regime, the
chain approaches in the course of time the expected energy equipartition among
the dipoles. For excitations of higher energy, strongly localized excitations
appear whose trajectories in time are either periodic or irregular, relating to
the well-known discrete or chaotic breathers, respectively. The phenomenon of
spontaneous formation of domains of opposite polarization and phase locking is
found to commonly accompany the time evolution of the chaotic breathers.
Finally, the sensitivity of the dipole chain dynamics to the initial conditions
is studied as a function of the initial excitation energy by computing a fast
chaos indicator. The results of this study confirm the aforementioned
approximate threshold value for the initial excitation energy, below which the
dynamics of the dipole chain is regular and above which it is chaotic.
