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Crystal Structure and Stoichiometric Composition of Potassium-Intercalated Tetracene.

ABSTRACT: The products of the solid-state reactions between potassium metal and tetracene (K:Tetracene, 1:1, 1.5:1, and 2:1) are fully structurally characterized. Synchrotron X-ray powder diffraction shows that only K2Tetracene forms under the reaction conditions studied, with unreacted tetracene always present for x < 2. Diffraction and 13C MAS NMR show that K2Tetracene has a crystal structure that is analogous to that of K2Pentacene, but with the cations ordered on two sites because of the influence of the length of the hydrocarbon on possible cation positions. K2Tetracene is a nonmagnetic insulator, thus further questioning the nature of reported superconductivity in this class of materials.

SUBMITTER: Hiley CI

PROVIDER: S-EPMC7482393 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Crystal Structure and Stoichiometric Composition of Potassium-Intercalated Tetracene.

Hiley Craig I CI Inglis Kenneth K KK Zanella Marco M Zhang Jiliang J Manning Troy D TD Dyer Matthew S MS Knaflič Tilen T Arčon Denis D Blanc Frédéric F Prassides Kosmas K Rosseinsky Matthew J MJ

Inorganic chemistry 20200811 17

The products of the solid-state reactions between potassium metal and tetracene (K:Tetracene, 1:1, 1.5:1, and 2:1) are fully structurally characterized. Synchrotron X-ray powder diffraction shows that only K2Tetracene forms under the reaction conditions studied, with unreacted tetracene always present for x < 2. Diffraction and 13C MAS NMR show that K2Tetracene has a crystal structure that is analogous to that of K2Pentacene, but with the cation ...[more]

PMID: 32805995

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