DOI: 10.1140/epje/i2002-10072-6
Pressure amorphization through displacive disorder
M.H. Cohen, J. Íñiguez and J.B. NeatonDepartment of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854-8019, USA mcohen@physics.rutgers.edu
(Received 29 march 2002 / Published online: 17 December 2002)
Abstract
After classifying amorphous materials according to their
topology, we review a recently proposed theory of pressure
amorphization (PA) that arises from some degree of displacive disorder
while retaining a crystalline topology. That theory is based on the
notion that one or more branches of the phonon spectrum become soft
and flat with increasing pressure and is illustrated by a simple model
that possesses the range of features displayed by many of the
materials which undergo PA with displacive disorder. We report the
results of Langevin simulations of the simple model which show how the
probability of amorphization increases with the number of unit cells
in the system and support our theory. We comment on how to generalize
the model for the study of real systems.
, 61.43.Fs Glasses
61.50.Ks - Crystallographic aspects of phase transformations; pressure effects.
64.70.Pf - Glass transitions.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2002
