Local order and thermal diffusivity in iron containing lime-phospho-silicate glass-ceramics

Thermal diffusivity, density, molar volume and electron paramagnetic resonance data on CaO-P2O5-SiO2-Fe2O3 glass-ceramics containing up to 30 mol% Fe2O3 are correlated in order to characterize the local order and thermal properties of the investigated system. The composition dependence of the thermal diffusivity at room temperature is consistent with the intermediate range order from the glass ceramics. The Fe3+-EPR data indicate that iron ions are disposed both in vitreous and crystallized phases but preponderantly in the last one.