Roland Bircher, Grégory Chaboussant, Stefan T. Ochsenbein, Felix Fernandez-Alonso, Hans U. Güdel and Euan K. Brechin
Inelastic neutron scattering study of undeuterated [Mn₉O₇(OAc)₁₁(thme)(py)₃(H₂O)₂]
Polyhedron 24, 2455-2458 (2005)                 

Abstract: We report on the magnetic properties of the enneanuclear mixed-valent single-molecule magnet [Mn₉O₇(OAc)₁₁(thme)(py)₃(H₂O)₂] (1). Using inelastic neutron scattering (INS) spectroscopy, we have confirmed the S = 17/2 cluster ground state of 1. Furthermore, we have determined accurately the anisotropy parameters of the zero field split ground state. The cluster 1 exhibits a strong negative axial anisotropy where D = -0.249(5) cm^–1. It is necessary to include an axial higher order term in the effective spin Hamiltonian to account for the experimental data.
Graphical Abstract: Inelastic neutron scattering spectra of the title compound have been measured at λ = 6.5  Å and T = 1.6 and 12 K, respectively. The peaks observed in this figure enabled accurate determination of the zero field splitting parameters of this single molecule magnet.