On the Density of Zirconium Dioxide

Measurement results of the density of asolid solution of fluorite type $\gamma$–$\mathrm{Zr}_{1 - a}$$\mathrm{Ca}_a\mathrm{O}_{2 – a}$ for the molar fraction range of the doping element $a = 0.05$--$0.25$ for samples being frozen from two equilibrium temperature values of $T = 1873$ and $2073$~K at a rate of $1000$ K/s (Fig. 1) were presented by A.M. Diness and R. Rustum [1] in 1965. Comparison with calculation results is also performed: (a) according to the model of the formation of oxygen vacancies in a lattice by its doping with inovalent cations; (b) according to the model of placement of all doping elements in interstitial sites of the lattice. Intrinsic "thermal") defects are assumed to absent in the lattice.