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DOE OSTI · 1777783

Predicting the Phase Stability of Multicomponent High-Entropy Compounds

Pitike, Krishna Chaitanya·KC, Santosh·Eisenbach, Markus·Bridges, Craig A.·Cooper, Valentino R.
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Abstract

A generic method to estimate the relative feasibility of formation of high-entropy compounds in a single phase, directly from first principles, is developed. As a first step, the relative formation abilities of 56 multicomponent, AO, oxides were evaluated. These were constructed from five cation combinations chosen from A = {Ca, Co, Cu, Fe, Mg, Mn, Ni, Zn}. Candidates for multicomponent oxides are predicted from descriptors related to the enthalpy and configurational entropy obtained from the mixing enthalpies of two-component oxides. The utility of this approach is evaluated by comparing the predicted combinations with the experimentally realized entropy-stabilized oxide, (MgCoCuNiZn)O. In the second step, Monte Carlo simulations are utilized to investigate the phase composition and local ionic segregation as a function of temperature. This approach allows for the evaluation of potential secondary phases, thereby making realistic predictions of novel multicomponent compounds that can be synthesized.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYcationsenthalpyentropyoxidessalts

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Pitike, Krishna Chaitanya, KC, Santosh, Eisenbach, Markus, Bridges, Craig A., Cooper, Valentino R.. 2020-07-31. Predicting the Phase Stability of Multicomponent High-Entropy Compounds. https://doi.org/10.1021/acs.chemmater.0c02702

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