The ionic conduction mechanism in 4CaO•P2O5 was investigated. It was found that the compound was a Ca-ion conductor at O partial pressures of between 10-5 and 105Pa and temperatures of between 1373 and 1873K, and under Ca vapor which was equilibrated using molten Ag-Ca.

K.Nagata: Solid State Ionics, 1996, 89[1-2], 169-75