A GENERAL-APPROACH FOR THE CALCULATION OF THE ENERGY-LEVELS AND THE INELASTIC NEUTRON-SCATTERING CROSS-SECTION OF HIGHLY NUCLEAR MAGNETIC CLUSTERS

We develop here a general approach to calculate in an efficient way th e spin levels as well as the spin eigenfunctions and the INS intensiti es of clusters formed by large numbers of exchange-coupled magnetic me tal ions. The approach is based on the successive use of the irreducib le tensor operator techniques and takes into account all kinds of magn etic exchange interactions between the metal ions. The potentialities of this approach are illustrated from an example comprising nine excha nge-coupled Ni (ii) ions.