Kim, Hyoungchul Ballikaya, Sedat Chi, Hang Ahn, Jae-Pyung Ahn, Kiyong Uher, Ctirad Kaviany, Massoud 2024-01-20T07:33:19Z 2024-01-20T07:33:19Z 2021-09-05 2015-03 1359-6454 https://pubs.kist.re.kr/handle/201004/125720 We demonstrate a prototype thermal evolution path for liquid thermal conductivity in solids. Thermal evolution of beta-Cu2Se shows large interstitial displacement of constituent atoms marked by glass-like transitions and an asymptotic liquid thermal transport. Using ab initio molecular dynamics (AIMD), we identify these transitions, and confirm them with in situ transmission electron microscopy and electron energy loss spectroscopy. The thermal disorder of the Cu+ ions forms homopolar Cu-Cu bonds under a rigid Se framework, and at yet higher temperatures the Se framework undergoes thermal distortion. The non-equilibrium AIMD prediction of lattice thermal conductivity shows significant suppression of the phonon transport, in agreement with experiments and molecular behavior. (C) 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. English PERGAMON-ELSEVIER SCIENCE LTD THERMOELECTRIC PERFORMANCE ELECTRON Ultralow thermal conductivity of beta-Cu2Se by atomic fluidity and structure distortion Article 10.1016/j.actamat.2014.12.008 1 ACTA MATERIALIA, v.86, pp.247 - 253 ACTA MATERIALIA 86 247 253 scie scopus 000349730900023 2-s2.0-84920760758 Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering Materials Science Metallurgy & Metallurgical Engineering Article THERMOELECTRIC PERFORMANCE ELECTRON Structure evolution Thermal conductivity Thermophysical property Thermoelectrics Phonon engineering