Odd and Even Numbered Ferric Wheels.

The structurally related odd and even numbered wheels [Fe III 11 Zn II 4 (tea) 10 (teaH) 1 (OMe)Cl 8 ] (1) and [Fe III 12 Zn II 4 (tea) 12 Cl 8 ] (2) can be synthesized under ambient conditions by reacting Fe III and Zn II salts with triethanolamine (teaH 3 ), the change in nuclearity being dictated by the solvents employed. An antiferromagnetic exchange between nearest neighbors, J = -10.0 cm -1 for 1 and J = -12.0 cm -1 for 2, leads to a frustrated S = 1/2 ground state in the former and an S = 0 ground state in the latter.