Record: found
Abstract: found
Article: not found

Elasticity of agr-Cristobalite: A Silicon Dioxide with a Negative Poisson's Ratio.

Author(s): A Haeri, John Parise, Lora Weidner

Publication date: 1992-07-31

Read this article at

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

Laser Brillouin spectroscopy was used to determine the adiabatic single-crystal elastic stiffness coefficients of silicon dioxide (SiO(2)) in the alpha-cristobalite structure. This SiO(2) polymorph, unlike other silicas and silicates, exhibits a negative Poisson's ratio; alpha-cristobalite contracts laterally when compressed and expands laterally when stretched. Tensorial analysis of the elastic coefficients shows that Poisson's ratio reaches a maximum value of -0.5 in some directions, whereas averaged values for the single-phased aggregate yield a Poisson's ratio of -0.16.