Impact of intrinsic localized modes of atomic motion on materials properties

Abstract

Recent neutron and x-ray scattering measurements show intrinsic localized modes (ILMs) in metallic uranium and ionic sodium iodide. Here, the role ILMs play in the behavior of these materials is examined. With the thermal activation of ILMs, thermal expansion is enhanced, made more anisotropic, and, at a microscopic level, becomes inhomogeneous. Interstitial diffusion, ionic conductivity, the annealing rate of radiation damage, and void growth are all influenced by ILMs. The lattice thermal conductivity is suppressed above the ILM activation temperature while no impact is observed in the electrical conductivity. This complement of transport properties suggests that ILMs could improve thermoelectric performance. Ramifications also include thermal ratcheting, a transition from brittle to ductile fracture, and possibly a phase transformation in uranium.

34 pages, 11 figures

References in corpus (6)

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• Observation of breathers in Josephson ladders
• Resonant States in the Electronic Structure of the High Performance Thermoelectrics AgPb${}_{m}SbTe$_{2+m}$ ; The Role of Ag-Sb Microstructures
• Intrinsic Localized Modes Observed in the High Temperature Vibrational Spectrum of NaI
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Cited by in corpus (6)

• Effect of discrete breathers on the specific heat of a nonlinear chain
• Effect of discrete breathers on macroscopic properties of the Fermi-Pasta-Ulam chain
• Discrete breathers in an array of self-excited oscillators: exact solutions and stability
• Rate theory of acceleration of the defect annealing driven by discrete breathers
• Low energy nuclear reactions driven by discrete breathers
• Unusual slow energy relaxation induced by mobile discrete breathers in one-dimensional lattices with next-nearest-neighbor coupling