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Prediction of entropy stabilized incommensurate phases in the system MoS2 -MoTe2.

ABSTRACT: A first principles phase diagram calculation, that included van der Waals interactions, was performed for the 3D bulk system (1 - X) · MoS2 - (X) · MoTe2. Surprisingly, the predicted phase diagram has at least two ordered phases, at X ? 0:46, even though all calculated formation energies are positive; in a ground-state analysis that examined all configurations with 16 or fewer anion sites. The lower-temperature I-phase is predicted to transform to a higher-temperature I'-phase at T ? 500 K, and I' disorders at T ? 730 K. Both these transitions are predicted to be first-order, and there are broad two-phase fields on both sides of the ordered regions. Both the I- and I'-phases are predicted to be incommensurate, i.e., aperiodic: I-phase in three dimensions; and I'-phase in two dimensions.

SUBMITTER: Burton BP

PROVIDER: S-EPMC5531295 | biostudies-other | 2016 Oct

REPOSITORIES: biostudies-other

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Prediction of entropy stabilized incommensurate phases in the system MoS2 -MoTe2.

Burton B P BP Singh A K AK

Journal of applied physics 20161018 15

A first principles phase diagram calculation, that included van der Waals interactions, was performed for the 3D bulk system (1 - X) · MoS2 - (X) · MoTe2. Surprisingly, the predicted phase diagram has at least two ordered phases, at X ≈ 0:46, even though all calculated formation energies are positive; in a ground-state analysis that examined all configurations with 16 or fewer anion sites. The lower-temperature I-phase is predicted ...[more]

PMID: 28757659

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