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arXiv · 2009.12519

High-Throughput Design of Peierls and Charge Density Wave Phases in Q1D Organometallic Materials

Prakriti Kayastha·Raghunathan Ramakrishnan
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Abstract

Soft-phonon modes of an undistorted phase encode a material's preference for symmetry lowering. However, the evidence is sparse for the relationship between an unstable phonon wavevector's reciprocal and the number of formula units in the stable distorted phase. This "1/q*-criterion" holds great potential for the first-principles design of materials, especially in low-dimension. We validate the approach on the Q1D materials space containing 1199 ring-metal units and identify candidates that are stable in undistorted (1 unit), Peierls (2 units), charge density wave (3-5 units), or long wave (>5 units) phases. We highlight materials exhibiting gap-opening as well as an uncommon gap-closing Peierls transition, and discuss an example case stabilized as a charge density wave insulator. We present the data generated for this study through an interactive publicly accessible Big Data analytics platform (http://moldis.tifrh.res.in/data/rmq1d) facilitating limitless and seamless data-mining explorations.

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Prakriti Kayastha, Raghunathan Ramakrishnan. 2021-01-23. High-Throughput Design of Peierls and Charge Density Wave Phases in Q1D Organometallic Materials. https://doi.org/10.1063/5.0041717

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