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Updated: Apr 26, 2026

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Size-dependent vibronic coupling in α-Fe2O3
K R O'Neal1, J M Patete2, P Chen1
1Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA.
Abstract:
We report the discovery of finite length scale effects on vibronic coupling in nanoscale α-Fe2O3 as measured by the behavior of vibronically activated d-d on-site excitations of Fe(3+) as a function of size and shape. An oscillator strength analysis reveals that the frequency of the coupled symmetry-breaking phonon changes with size, a crossover that we analyze in terms of increasing three-dimensional character to the displacement pattern. These findings demonstrate the flexibility of mixing processes in confined systems and suggest a strategy for both enhancing and controlling charge-lattice interactions in other materials.
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