Landau mean-field model with the cubic term for the $$\upalpha $$–$$\upbeta $$ transition in quartz

Thermodynamic quantities are calculated as a function of temperature by using Landau mean-field model for the $$\upalpha $$ – $$\upbeta $$ transition in quartz. By expanding the Gibbs free energy in terms of the order parameter (Q) with the cubic term ( $$Q³),$$ the temperature dependence of the relevant thermodynamic quantities are predicted using the heat capacity ( $$C_{\mathrm {P}})$$ , which is fitted to the experimental data from the literature for the $$\upalpha $$ – $$\upbeta $$ transition in quartz. Our results indicate that the Landau mean-field model is adequate to describe the first-order $$\upalpha $$ – $$\upbeta $$ transition in quartz.