Many-Spin Interactions and Spin Excitations in Mn12
  In this work, the many-spin interactions taking place in Mn12 large-spin clusters are extensively studied using the 8-spin model Hamiltonian, for which we determine the possible parameters based on experimental data. Account of the many-spin excitations satisfactorily explains positions of the neutron scattering peaks, results of EPR measurements and the temperature dependence of magnetic susceptibility. In particular, strong Dzyaloshinsky-Morya interactions are found to be important for description of neutron scattering data. The role of these interactions for the relaxation of the magnetization is qualitatively discussed. 
M. I. Katsnelson, V. V. Dobrovitski and B. N. Harmon