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Cr4US8 is prepared by reaction of a 1:1:6 molar mixture of U, Cr, and S in a PbI2 flux (1073 K, 12 h; 75% yield).

The new uranium(IV) chlorophosphate compounds UCl4(POCl3) and [U2Cl9][PCl4] have been synthesized by the solid-state reactions of U, P2O5, and PCl5 at 648 K; the compounds UCl3(PO2Cl2) and U2Cl8(POCl3) have been synthesized at 648 K with the same reactants plus added S. Their structures are, respectively, chainlike, a simple salt, three-dimensional, and sheetlike. From ab initio calculations, U2Cl8(POCl3) and UCl3(PO2Cl2) are found to be ferromagnetic, whereas UCl4(POCl3) is found to be antiferromagnetic. U2Cl8(POCl3) is a strong metal, whereas UCl3(PO2Cl2) is a weaker metal. In contrast, UCl4(POCl3) has a finite band gap, with a value of 0.35 eV.

The Synthesis and Characterization of Four New Uranium(IV) Chlorophosphates: UCl 4(POCl3), [U2Cl9][PCl4], UCl3(PO2Cl2), and U2Cl8(POCl3). -Under identical conditions, the solid state reaction of (I) and (II) in the absence of sulfur leads to the formation of (IV) in a first run and (V) in a second run. The crystal structures of compounds (IV)-(VII) are determined by single crystal XRD. (IV) crystallizes in the monoclinic space group P2 1/c with Z = 4, (V) in the orthorhombic space group Pccn with Z = 4, (VI) in the orthorhombic space group Pbam with Z = 8, and (VII) in the orthorhombic space group Pnma with Z = 4. The structures are chainlike for (IV), a simple salt for (V), three-dimensional for (VI), and sheetlike for (VII), respectively. DFT calculations show that (VI) and (VII) are ferromagnetic, whereas (IV) is antiferromagnetic. Compound (VII) is a strong and compound (VI) a weak metal. (IV) exhibits a finite band gap of 0.35 eV. -(WARD, M. D.; CHAN, I. Y.; LEBEGUE, S.; IBERS*, J. A.; Inorg. Chem. 53 (2014) 18, 9969-9975, http://dx.doi.org/10.1021/ic501781h ; Dep. Chem., Northwest. Univ., Evanston, IL 60208, USA; Eng.) -W. Pewestorf 46-016