title: Three new quaternary actinide chalcogenides Ba2TiUTe7, Ba2CrUTe7, and Ba2CrThTe7: syntheses, crystal structures, transport properties, and theoretical studies.
abstract: The three new quaternary actinide chalcogenides Ba2TiUTe7, Ba2CrUTe7, and Ba2CrThTe7 have been synthesized. From single-crystal X-ray diffraction studies these isostructural compounds are found to crystallize in a new structure type in space group D2h16–Pnma of the orthorhombic system. The structure features ∞1[MAnTe74–] strips (M = Cr or Ti; An = Th or U) that propagate in the b-direction and are separated by Ba cations. An atoms are coordinated to eight Te atoms in a bicapped trigonal-prismatic geometry while M atoms are octahedrally coordinated to six Te atoms. Sharing of the AnTe8 and MTe6 polyhedra forms ∞1[MAnTe74–] strips. The presence of the infinite linear Te–Te–Te chains in these compounds makes assignment of oxidation states arbitrary. Resistivity measurements and DFT calculations provide further insight into the properties of these compounds.
authors: †Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States.
authors: Jai
authors: J
authors: Prakash
authors: †Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States.|‡ICSM, UMR 5257 CEA/CNRS/UM2/ENSCM, Site de Marcoule-Bât. 426, BP 17171, 30207 Bagnols-sur-Cèze Cedex, France.
authors: Adel
authors: A
authors: Mesbah
authors: †Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States.
authors: Jessica
authors: J
authors: Beard
authors: §Laboratoire de Cristallographie, Résonance Magnétique et Modélisations (CRM2, UMR CNRS 7036), Institut Jean Barriol, Université de Lorraine, BP 239, Boulevard des Aiguillettes, 54506 Vandoeuvre-lès-Nancy, France.
authors: Sébastien
authors: S
authors: Lebègue
authors: †Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States.
authors: Christos D
authors: CD
authors: Malliakas
authors: †Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States.
authors: James A
authors: JA
authors: Ibers