A metastable amorphous intermediate is responsible for laser-induced nucleation of glycine

Liao, Z. and Wynne, K. (2022) A metastable amorphous intermediate is responsible for laser-induced nucleation of glycine. Journal of the American Chemical Society, 144(15), pp. 6727-6733. (doi: 10.1021/jacs.1c11154) (PMID:35384650)

Abstract

Laser-induced crystal nucleation through optical tweezing, and in particular polymorph selection through laser polarization, promises unprecedented control over crystallization. However, in the absence of a nearby liquid–liquid critical point or miscibility gap, the origin of the required mesoscale clusters remains unclear. A number of recent studies of so-called nonclassical nucleation have suggested the presence of large amorphous clusters. Here, we show that supersaturated aqueous glycine solutions form metastable intermediate particles that are off the direct path to crystal nucleation. Laser-induced crystal nucleation only occurs when the laser “activates” one of these particles. In situ low-frequency Raman spectroscopy is used to demonstrate their amorphous or partially ordered character and transformation to various crystal polymorphs. The requirement for solution aging in many previously reported laser-induced crystal nucleation experiments strongly suggests that the presence of amorphous intermediates is a general requirement.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Liao, Dr Zhiyu and Wynne, Professor Klaas
• Authors: Liao, Z., and Wynne, K.
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: Journal of the American Chemical Society
• Publisher: American Chemical Society
• ISSN: 0002-7863
• ISSN (Online): 1520-5126
• Published Online: 06 April 2022
• Copyright Holders: Copyright © 2022 American Chemical Society
• First Published: First published in Journal of the American Chemical Society 144(15):6727–6733
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
166308		Liquid-liquid transitions in molecular liquids: from supramolecular structure to phase separation	Klaas Wynne	Engineering and Physical Sciences Research Council (EPSRC)	EP/J004790/1	Chemistry
190480		University of Glasgow - Equipment Account	Muffy Calder	Engineering and Physical Sciences Research Council (EPSRC)	EP/J014478/1	S&E - College Senior Management
304469		CONTROL	Klaas Wynne	European Commission (EC)	832703	Chemistry