Short intense laser pulses of visible and infrared light can dramatically accelerate crystal nucleation from transparent solutions; previous studies invoke mechanisms that are only applicable for nucleation of ordered phases or high dielectric phases. However, we show that similar laser pulses induce CO2bubblenucleation in carbonated water. Additionally, in water that is cosupersaturated with argon and glycine, argon bubbles escaping from the water can induce crystal nucleation without a laser. Our findings suggest a possible link between laser-induced nucleation of bubbles and crystals.
B. C. Knott, J. L. LaRue, A. M. Wodtke, M. F. Doherty, B. Peters, Communication: Bubbles, crystals, and laser-induced nucleation, J. Chem. Phys. 2011, 134, 171102, DOI: 10.1063/1.3582897
FIG. 1. Bubbles form along the laser beam line in response to a single laser pulse. The supersaturation was c/c sat = 2.50. The laser produced 280 mJ/pulse at a wavelength of 532 nm, far above the threshold for laser-induced bubble nucleation.
Figure-2.pptx (79 kB)
FIG. 2. Supersaturation dependence of the threshold laser pulse energy to induce bubble nucleation in aqueous carbon dioxide solutions at three different laser wavelengths. The “ultrapure” solutions are prepared with 99.999% pure CO2 and ultrapure H2O; “tap” solutions are prepared with 99.5% pure CO2 and municipal tap H2O.
Figure-3.pptx (299 kB)
FIG. 3. Bubble-induced crystallization. Panels (a) and (b) show glycine crystal formation from a solution that is supersaturated with both glycine and argon and then shaken, whereas panels (c) and (d) show an absence of crystal formation when argon is absent.
American Institute of Physics