An experimental investigation, using techniques that included alternating-current and direct-current electrical conductivity, calorimetric and Raman scattering measurements, was carried out on a monocrystalline sample. This led to the proposal of a different structure for such compounds. The structure was compatible with the ionic conductivity and thermal behavior of the present system. Piezo-electric resonances and Raman selection rules supported the proposed non centro-symmetrical group. A set of conduction mechanisms was proposed that described the highly anisotropic conductivity of the crystal.

Ionic Conductivity and Crystalline Structure of Li2CaHfF8 Crystals. A.P.Ayala, I.Guedes, P.T.C.Freire, J.M.Sasaki, J.Mendes Filho, J.Y.Gesland, R.L.Moreira: Solid State Ionics, 2000, 136-137, 345-50