Spectroscopic measurement of electronic temperature in the bubbles during single- and multibubble sonoluminescence of metal carbonyl solutions and nanodispersed suspensions.

It is for the first time that we have obtained emission-line spectra of metal atoms during single-bubble sonoluminescence of metal carbonyl W(CO)6, Mo(CO)6, Cr(CO)6 solutions in dodecane and similar spectra during single- and multibubble sonoluminescence of nanodispersed Cr(CO)6 suspensions in water, 83% H2SO4 and 74% H3PO4. Nanodispersed suspensions with an average particle size of 15-20 nm were obtained through sonodispersing and filtering Cr(CO)6 crystals in water. The method for comparing the intensities of two atomic metal lines made it possible to measure the electronic temperatures achieved in cavitation bubbles under different modes of sonolysis that vary in the range of (4.5-16)·103 K depending on the mode of sonolysis, the type of liquid and saturating gas (He, Ar, Kr) and the acoustic energy entering the solution or suspension. The electronic temperature for multibubble sonoluminescence is, on the average, by (2-2.5)·103 K less than for single-bubble sonoluminescence for all liquids in question.