A Novel Ferromagnet: Cal4MnBi11

Magnetic susceptibility and electrical resistivity measurements have been made on the Zintl compound, Cal4MnBi11, for temperatures between 6 K and 300 K. The magnetic data are consistent with high spin Mn+3 for T < 100 K and a ferromagnetic transition is observed at ∼56 K. Although the Mn+3 ion has four unpaired spins in the paramagnetic regime, the ferromagnetic moment is considerably reduced. Resistivity data also display a transition at approximately 56 K.