Molecular and atomic emission during single-bubble cavitation in concentrated sulfuric acid

Concentrated acid solutions have been reported to produce bright light emission during cavitation. Single-bubble sonoluminescence (SBSL) from sulfuric acid (H ₂SO ₄) is much brighter than SBSL from water by over three orders of magnitude when both are regassed with Ar. In contrast to water, SBSL spectra of concentrated H ₂SO ₄ contain extensive atomic, molecular, and ionic emission revealing details about intracavity physical conditions and chemical processes. Observation of specific emitters coupled with detailed studies of the temporal emission of the emitters relative to one another and to the overall bubble oscillation will lead to a much more detailed understanding of SBSL.