Heisenberg dimer single molecule magnets in a strong magnetic field

We calculate the static and dynamic properties of single crystal, single molecule magnets consisting of equal spin S=1/2 or 5/2 dimers. The spins in each dimer interact with each other via the Heisenberg exchange interaction and with the magnetic induction B via the Zeeman interaction, and interdimer interactions are negligible. For antiferromagnetic couplings, the static magnetization and specific heat exhibit interesting low-temperature T and strong B quantum effects. We calculate the frequency spectrum of the Fourier transform of the real part of the time autocorrelation function C-11(t) for arbitrary T, B, and compare our results with those obtained for classical spins. We also calculate the inelastic neutron magnetic dynamical structure factor S(q,omega) at arbitrary T, B.