Unstable diffusion and chemical dissociation of a single sonoluminescing bubble.

In a certain parameter region, a single sonoluminescencing bubble is unstable against diffusion of gases and their chemical dissociation. Experiments show that a surface unstable bubble emits a microbubble and recoils. After this it exhibits specific dynamical features whereby the ambient radius changes in a nonmonotonic way. A numerical analysis identifies the phenomenon as the result of the interplay between spatial translations and induced variations of driving pressure on one side and the chemical composition of gases in the bubble on the other side. The results confirm that dynamical chemical dissociation phenomena as well as acoustic properties play an important role in the understanding of single-bubble sonoluminescence.