Exchange integrals and single-ion anisotropy parameters of a ring-shaped molecular cluster, comprising eight chromium(III) ions $\mathrm{}(s=3/2\mathrm{})\mathrm{}$ were determined by inelastic neutron scattering. Effects due to the mixing of different spin multiplets have been considered. Such effects proved to be important to correctly reproduce the relative intensity of magnetic excitations in the neutron spectra. Evidence of decreasing lifetimes with increasing energy of excited spin states was found. The microscopic picture emerging from neutron spectroscopy was confirmed by the temperature dependence of the heat capacity.

Combining recent and new inelastic neutron scattering data for the molecular cyclic cluster ${\mathrm{C}\mathrm{r}}_8$ produces a deep understanding of the low lying excitations in bipartite antiferromagnetic Heisenberg rings. The existence of the $L$ band, the lowest rotational band, and the $E$ band, essentially spin wave excitations, is confirmed spectroscopically. The different significance of these excitations and their physical nature is clearly established by high-energy and $Q$-dependence data.

Inelastic neutron scattering has been applied to the study of the spin dynamics of Cr-based antiferromagnetic octanuclear rings where a finite total spin of the ground state is obtained by substituting one ${\mathrm{Cr}}^{3+}$ ion $(s=3∕2)$ with $\mathrm{Zn}(s=0)$, $\mathrm{Mn}(s=5∕2)$, or $\mathrm{Ni}(s=1)$ dications. Energy and intensity measurements for several intramultiplet and intermultiplet magnetic excitations allow us to determine the spin wave functions of the investigated clusters. Effects due to the mixing of different spin multiplets have been considered. Such effects proved to be important to correctly reproduce the energy and intensity of magnetic excitations in the neutron spectra. On the contrary to what is observed for the parent homonuclear ${\mathrm{Cr}}_8$ ring, the symmetry of the first excited spin states is such that anticrossing conditions with the ground state can be realized in the presence of an external magnetic field. Heterometallic ${\mathrm{Cr}}_{7}M$ wheels are therefore good candidates for macroscopic observations of quantum effects.