Abstract
[Mn3O(OAc)7(HOAc)]6·xAcOH (x = 6-9) represents a rare example of a compound containing molecular Mn18-rings. These are formed by Mn3(µ3-O) subunits in which the high-spin Mn(III) centers are bridged by three pairs of acetate anions (AcO-). An AcOH molecule coordinates to one of the Mn atoms leading to [Mn3(µ3-O)(µ2-OAc)6(AcOH)]-units, designated in short as Mn3-units, that are interconnected by acetate anions via the other two Mn atoms to form Mn18-rings. Magnetic measurements show weak ferromagnetic interactions between them that are suppressed in strong magnetic field. Quantum-chemical calculations on Mn3 model complexes using independently DFT and ab-initio multi reference methods (CASSCF/NEVPT2) show a correlation between the orientation of the pseudo-Jahn-Teller axes of pairs of Mn(III) magnetic centers and corresponding exchange coupling energies. Weak coupling between Mn3-units within the Mn18-ring allowed to simulate the magnetic susceptibility vs temperature dependence in terms of basically uncoupled magnetic moments of each Mn3-unit within the ring.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
