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Superconductivity in Crystallographically Disordered LaHg_6.4.

ABSTRACT: The influence of structural disorder on superconductivity is not yet fully understood. A concurrent examination of crystallographic and physical properties of LaHg_6.4 reveals that this material enters a superconducting state below T_c = 2.4 K while showing crystallographic disorder in one dimension. Lanthanum mercuride, which crystallizes in a new structure type (space group Cmcm, a = 9.779(2) Å, b = 28.891(4) Å, c = 5.0012(8) Å, Z = 8), has remained out of reach for nearly 50 years. In this crystal structure, strong disorder is present in the channels that propagate along the [001] direction. By implementing a combination of cutting-edge synthesis and characterization techniques, we were able to circumvent the complexity associated with the low formation temperature and chemical reactivity of this substance and study the superconductivity of LaHg_6.4 in detail.

SUBMITTER: Prots Y

PROVIDER: S-EPMC9533302 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Superconductivity in Crystallographically Disordered LaHg6.4.

Prots Yurii Y Krnel Mitja M Grin Yuri Y Svanidze Eteri E

Inorganic chemistry 20220902 39

The influence of structural disorder on superconductivity is not yet fully understood. A concurrent examination of crystallographic and physical properties of LaHg6.4 reveals that this material enters a superconducting state below Tc = 2.4 K while showing crystallographic disorder in one dimension. Lanthanum mercuride, which crystallizes in a new structure type (space group Cmcm, a = 9.779(2) Å, b = 28.891(4) Å, c = 5.0012(8) Å, Z = ...[more]

PMID: 36053961

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