Science. 1992 Jul 31;257(5070):650-2. doi: 10.1126/science.257.5070.650.
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.
激光布里渊光谱学被用于测定二氧化硅（SiO(2)）的各向同性单晶弹性弹性系数在石英结构。这种 SiO(2)多晶型，与其他的硅石和硅酸盐不同，表现出负泊松比；石英在压缩时横向收缩，拉伸时横向膨胀。弹性系数张量分析表明，泊松比在某些方向上达到最大值-0.5，而单相聚合体的平均值则产生泊松比-0.16。
