A Determination of the Elastic Moduluss13of Beta-Quartz

The adiabatic Young's modulus of beta-quartz along a direction at 45 degrees to the optic axis has been measured as a function of temperature. These data, in conjunction with that of Atanasoff and Kammer, and of Perrier and de Mandrot, yield a value for the adiabatic elastic modulus $s_{13}$ of beta-quartz equal to -0.226 × ${10}^{-12\mathrm{}}$ ${\mathrm{cm}}^2$/dyne at 600°C and indicate that the value reported by Osterberg and Cookson for $c_{44}$ is inconsistent with the stability of beta-quartz.