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arXiv · 1808.01794

Large entropy change derived from the orbitally assisted three-centered two-electron σ bond formation in a metallic Li0.33VS2

N. Katayama·S. Tamura·T. Yamaguchi·K. Sugimoto·K. Iida·T. Matsukawa·A. Hoshikawa·T. Ishigaki·S. Kobayashi·Y. Ohta·H. Sawa
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Abstract

We discuss herein the emergence of a large entropy change in metallic Li0.33VS2 derived from the orbitally assisted loose σ bond formation. Comprehensive structural studies based on synchrotron x-ray and neutron diffraction analyses clarify the fabrication of ribbon chains at 375 K, consisting of multiple three-centered two-electron σ bonds based on the viewpoint of local chemical bonding. Although the metallic conductivity persists down to the lowest temperature measured, exceptionally large entropy change as a metal, as much as ΔS = 6.6 J/mol K, appears at the transition. Emergence of a large entropy change in a metallic state expects us the possible novel functional materials, such as a heat-storage material with rapid thermal response.

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N. Katayama, S. Tamura, T. Yamaguchi, K. Sugimoto, K. Iida, T. Matsukawa, A. Hoshikawa, T. Ishigaki, S. Kobayashi, Y. Ohta, H. Sawa. 2018-08-06. Large entropy change derived from the orbitally assisted three-centered two-electron σ bond formation in a metallic Li0.33VS2. https://doi.org/10.1103/physrevb.98.081104

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