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

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.

6 pages, 4 figures, to be published in Phys. Rev. B: Rapid Communications