Magnon spectrum of transition-metal oxides: Calculations including long-range magnetic interactions using the LSDA+U method

We present LSDA+U calculations of the magnon frequencies of transition-metal monoxides (TMOs) using the frozen magnon approach. We systematically vary U to investigate the effect of the on-site Coulomb repulsion on various properties such as the gap, the magnetic moment, and the magnon energies. For all TMOs, a similar behavior of the gap and moment with respect to U is found: the gaps start to increase linear and saturate for large U. The moment is enhanced by ∼0.4μ_B towards the pure spin limit. Magnon energies are strongly suppressed on increasing the on-site Coulomb repulsion. The reason for this behavior is related to charge localization.