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Settling the matter of the role of vibrations in the stability of high-entropy carbides.

ABSTRACT: High-entropy ceramics are attracting significant interest due to their exceptional chemical stability and physical properties. While configurational entropy descriptors have been successfully implemented to predict their formation and even to discover new materials, the contribution of vibrations to their stability has been contentious. This work unravels the issue by computationally integrating disorder parameterization, phonon modeling, and thermodynamic characterization. Three recently synthesized carbides are used as a testbed: (HfNbTaTiV)C, (HfNbTaTiW)C, and (HfNbTaTiZr)C. It is found that vibrational contributions should not be neglected when precursors or decomposition products have different nearest-neighbor environments from the high-entropy carbide.

SUBMITTER: Esters M

PROVIDER: S-EPMC8484556 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Settling the matter of the role of vibrations in the stability of high-entropy carbides.

Esters Marco M Oses Corey C Hicks David D Mehl Michael J MJ Jahnátek Michal M Hossain Mohammad Delower MD Maria Jon-Paul JP Brenner Donald W DW Toher Cormac C Curtarolo Stefano S

Nature communications 20210930 1

High-entropy ceramics are attracting significant interest due to their exceptional chemical stability and physical properties. While configurational entropy descriptors have been successfully implemented to predict their formation and even to discover new materials, the contribution of vibrations to their stability has been contentious. This work unravels the issue by computationally integrating disorder parameterization, phonon modeling, and thermodynamic characterization. Three recently synthe ...[more]

PMID: 34593798

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