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Updated: Aug 7, 2026

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Mesostructures of cobalt nanocrystals. 1. Experiment and theory
V Germain1, J Richardi, D Ingert
1Laboratoire des Matériaux Mesoscopiques et Nanométriques U.M.R. 7070, Université Pierre et Marie Curie, BP 52, 4 place Jussieu, 75005 Paris, France.
Abstract:
Solid mesostructures made of cylinders are produced by the slow evaporation of cobalt nanocrystals dispersed in hexane and subjected to an applied field perpendicular to the substrate. Varying the initial nanocrystal concentration is found to be an efficient method for changing the pattern size. The experimental structures and the theoretical predictions based on the minimization of the total free energy are in good agreement. A comparison of experiment with theory allowed us to conclude that the mesostructures form as a result of a liquid-gas phase transition during the evaporation process. Within the theoretical model and the experimental data, it is concluded that the phase ratio of the magnetic to the total volume and the height of the cylinders govern the pattern geometry. In contrast, because of the saturation of the magnetization curve, the mesostructures are not influenced by the field strength.
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