Nucleation in Aqueous KCl Solutions Induced by Laser Pulses

12 Sept 2019, 14:20
20m

Speaker

Renato Torre (European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, Italy; Dip. di Fisica ed Astronomia; Università di Firenze, Italy)

Description

The nucleation processes are still today between the more intriguing problems of the condensed matter physics; they have been described by different models, but their understanding I still far to be complete [1]. In particular, we are missing the experimental investigations of the first nucleation events due to their unpredictable localization in the time and space coordinates.
The nucleation in saturated solutions can be induced by a short laser pulse of high intensity [2]; a series of experimental studies have proved that this phenomenon occur in aqueous solutions of very different nature, where the solutes can vary from simple salts to complex biological molecules [3]. Even if the NonPhotochemical Laser Induced Nucleation (NPLIN) is known from more than 20 years, several fundamental aspects of it remain open problems [4]. Nevertheless, the NPLIN enables the possibility to perform spectroscopic measurements during the first steps of crystal nucleation and growth, opening the harvesting of new valuable information on this elusive phenomenon.
We performed an experimental investigation of the nucleation phenomena induced by a 25 picosecond infrared laser pulse in a supersaturated aqueous KCl solution. In particular, we developed an experimental set-up able to perform a very fast imaging (up to 5*105 frame/sec) of the solution modifications induced by the laser pulse. The fast imaging shows a series of physical processes taking place in the solution between the laser pulse arrival and the show up of the crystal nucleus.
[1] Kelton, K. F.; Frenkel, D. Preface: Journal of Chemical Physics 2016, 145 (21).
[2] Garetz, B. A.; Aber, J. E.; Goddard, N. L.; Young, R. G.; Myerson, A. S. Physical Review Letters 1996, 77 (16), 3475.
[3] Li, W.; Ikni, A.; Scouflaire, P.; Shi, X.; El Hassan, N.; Gémeiner, P.; Gillet, J.-M.; Spasojević-de Biré, A. Cryst Growth Des 2016, 16 (5), 2514.
[4] Kacker, R.; Dhingra, S.; Irimia, D.; Ghatkesar, M. K.; Stankiewicz, A.; Kramer, H. J. M.; Eral, H. B. Cryst Growth Des 2018, 18 (1), 312.

Topic 1. Amorphous and soft matter

Primary author

Renato Torre (European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, Italy; Dip. di Fisica ed Astronomia; Università di Firenze, Italy)

Co-authors

Dr Andrea Taschin (European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, Italy; Dip. di Fisica ed Astronomia; Università di Firenze, Italy) Dr Paolo Bartolini (European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, Italy; ) Stefano Benci (LENS - Università degli Studi di Firenze)

Presentation materials

There are no materials yet.