  We report cold-neutron inelastic neutron scattering measurements on
deuterated samples of the giant polyoxomolybdate magnetic molecule {Mo72Fe30}.
The 30 s = 5/2 Fe+3 ions occupy the vertices of an icosidodecahedron, and
interact via antiferromagnetic nearest neighbor coupling. The measurements
reveal a band of magnetic excitations near E ~ 0.6 meV. The spectrum broadens
and shifts to lower energy as the temperature is increased, and also is
strongly affected by magnetic fields. The results can be interpreted within the
context of an effective three-sublattice spin Hamiltonian.
