Logarithmic Kinetics of the Amorphous-Amorphous Transformations in <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>SiO</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span> and <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>GeO</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span> Glasses under High Pressure

O. B. Tsiok; V. V. Brazhkin; A. G. Lyapin; L. G. Khvostantsev

doi:10.1103/PhysRevLett.80.999

Logarithmic Kinetics of the Amorphous-Amorphous Transformations in ${SiO}_{2}$ and ${GeO}_{2}$ Glasses under High Pressure

O. B. Tsiok, V. V. Brazhkin, A. G. Lyapin, and L. G. Khvostantsev

Phys. Rev. Lett. 80, 999 – Published 2 February 1998

Abstract

We have studied in situ the kinetics of the amorphous-amorphous coordination transformation in ${GeO}_{2}$ glass and of the initial stage of transformation in vitreous ${SiO}_{2}$ up to 9 GPa by volume vs time measurements using the precise strain-gauge technique. The volume vs time dependence at all pressure points was found to obey the logarithmic law, which distinguishes the observed transformation kinetics from that of the ordinary transitions in crystals. The first evidence of anelastic behavior was found from the quasistatic equation of state at $P \approx 6 - 7$ GPa for ${SiO}_{2}$ glass and at 2–3 GPa for ${GeO}_{2}$ glass, i.e., at lower pressures than previously believed.