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Published on: January 17, 2017
Metal Transition in Sodium-Ammonia Nanodroplets
Sebastian Hartweg1, Adam H C West1, Bruce L Yoder1
1Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland.
Abstract:
The famous nonmetal-to-metal transition in Na-ammonia solutions is investigated in nanoscale solution droplets by photoelectron spectroscopy. In agreement with the bulk solutions, a strong indication for a transition to the metallic state is found at an average metal concentration of 8.8±2.2 mole%. The smallest entity for the phase transition to be observed consists of approximately 100-200 solvent molecules. The quantification of this critical entity size is a stepping stone toward a deeper understanding of these quantum-classical solutions through direct modeling at the molecular level.
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