Structures and Magnetic Properties of K2Pd4U6S17, K2Pt4U6S17, Rb2Pt4U6S17, and Cs2Pt4U6S17 Synthesized Using the Boron-Chalcogen Mixture Method

Logan S Breton; Ryan Baumbach; Hunter B Tisdale; Hans-Conrad Zur Loye

doi:10.1021/acs.inorgchem.2c01363

Structures and Magnetic Properties of K₂Pd₄U₆S₁₇, K₂Pt₄U₆S₁₇, Rb₂Pt₄U₆S₁₇, and Cs₂Pt₄U₆S₁₇ Synthesized Using the Boron-Chalcogen Mixture Method

Inorg Chem. 2022 Jul 11;61(27):10502-10508. doi: 10.1021/acs.inorgchem.2c01363. Epub 2022 Jun 29.

Authors

Logan S Breton¹, Ryan Baumbach², Hunter B Tisdale¹, Hans-Conrad Zur Loye¹

Affiliations

¹ Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States.
² Department of Physics and National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32306, United States.

PMID: 35766156
DOI: 10.1021/acs.inorgchem.2c01363

Abstract

A series of A₂M₄U₆S₁₇ (A = alkali metal; M = Pd, Pt) compounds, specifically K₂Pd₄U₆S₁₇, K₂Pt₄U₆S₁₇, Rb₂Pt₄U₆S₁₇, and Cs₂Pt₄U₆S₁₇, were synthesized using the combined boron-chalcogen mixture and molten flux crystal growth methods. The formation of rubidium- and cesium-containing analogues resulted from a in situ alkali polysulfide flux formed from alkali carbonates. The successful synthesis of single crystals of the title compounds allowed for their structural characterization by single-crystal X-ray diffraction. The structure determination revealed disorder of the alkali cations in Rb₂Pt₄U₆S₁₇ and Cs₂Pt₄U₆S₁₇, while the potassium cations in K₂Pd₄U₆S₁₇ and K₂Pt₄U₆S₁₇ were fully ordered. Magnetic measurements were performed on samples of K₂Pt₄U₆S₁₇, Rb₂Pt₄U₆S₁₇, and Cs₂Pt₄U₆S₁₇ that contained small amounts of paramagnetic β-US₂ and diamagnetic PtS. Antiferromagnetic order was observed at T_N = 9.1 K for K₂Pt₄U₆S₁₇. No long-range magnetic order was observed for Rb₂Pt₄U₆S₁₇ and Cs₂Pt₄U₆S₁₇. Uranium moments of 2.5, 2.6, and 2.6 μ_B were measured for K₂Pt₄U₆S₁₇, Rb₂Pt₄U₆S₁₇, and Cs₂Pt₄U₆S₁₇, respectively.