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DOE OSTI · 1673296

Superstructures and Superconductivity Linked with Pd Intercalation in Nb 2 Pd x Se 5

Neu, Jennifer·Graf, David·Wei, Kaya·Gaiser, Alyssa·Xin, Yan·Lai, You·Albrecht-Schmitt, Thomas E.·Baumbach, Ryan·Singh, David J.·Siegrist, Theo
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Abstract

Single crystals of Nb 2 Pd x Se 5 have been grown covering a broad range of palladium stoichiometries, from x = 0.68 to x = 0.95 (Pd2 occupancies 0.36 and 0.90 respectively). Miscibility gaps in the Pd stoichiometry range are related to superstructures resulting from staged filling and ordering of the partially filled Pd atom site (Pd2, Wyckoff site 2a). For Pd2 near 1/2 occupancy, a superstructure based on an incommensurate occupation wave with modulation along the monoclinic b-axis is identified. Here, a superconducting dome is found for Pd2 occupancies above 0.58, with maximum Tc for Pd2 occupancy of approximately 2/3. DFT calculations for the fully and 1/2 occupied Pd2 site show that Nb 2 Pd x Se 5 can be considered an intercalation compound for Pd2 occupancy above the minimum required for structural stability.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYCrystal structureMathematical methodsPalladiumSuperstructuresTransition metals

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BibTeXRIS

Neu, Jennifer, Graf, David, Wei, Kaya, Gaiser, Alyssa, Xin, Yan, Lai, You, Albrecht-Schmitt, Thomas E., Baumbach, Ryan, Singh, David J., Siegrist, Theo. 2020-09-02. Superstructures and Superconductivity Linked with Pd Intercalation in Nb 2 Pd x Se 5. https://doi.org/10.1021/acs.chemmater.0c02291

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