12142-69-7Relevant articles and documents
High-pressure synthesis, structure and properties of new ternary pnictides La3TiX5 (X = P, As)
Cao, Lipeng,Deng, Zheng,Duan, Lei,Jin, Changqing,Li, Wenmin,Li, Zhi,Wang, Xiancheng,Yu, Runze,Zhang, Jun,Zhao, Jianfa
, (2020)
The new ternary pnictides La3TiX5 (X = P, As) and the solid solutions of La3Ti(Sb1-xAsx)5 (x = 0–1) and La3Ti(As1-yPy)5 (y = 0–1) were synthesized under high pressure and high temperature conditions. The crystal structure of La3TiX5 (X = P, As) was determined from the X-ray powder diffraction data. These compounds crystallize in a hexagonal Hf5Sn3Cu-anti type structure with the space group P63/mcm and lattice parameters a = 8.7927 ? and c = 5.7643 ? for La3TiP5, and a = 9.0267 ? and c = 5.9071 ? for La3TiAs5, in which the face-sharing TiX6 octahedral chains running along the c axis are separated by La3+ in the interstice sites with a distance about 9 ?, presenting a strong one-dimensional crystal structure. Physical properties measurements indicate La3TiX5 (X = P, As) are Pauli paramagnetic metals. The calculations reveal that La3+ ions are not perfectly ionic owing to the non-negligible contributions of La to the density of state (DOS) at the Fermi level and bridge the X atoms between the chains, which make the samples to be 3-dimensional metals. What's more, the change of X in La3TiX5 from Sb to P increases the ionicity of La3+ and thus decreases the electron hopping between the conducting chains.
La6Pd2+xSb15 (x = 0.28): A rare-earth palladium intermetallic compound with extended pnictogen ribbons
Amigó, M. Lourdes,Aswartham, Saicharan,Büchner, Bernd,Caglieris, Federico,Facio, Jorge I.,Hess, Christian,Seiro, Silvia,Sturza, Mihai I.,Wurmehl, Sabine,van den Brink, Jeroen
, (2020)
A new intermetallic ternary compound La6Pd2.28Sb15 was synthesized from the reaction of lanthanum and palladium metals in a molten antimony flux. The compound crystallizes in the orthorhombic space group Immm with a ?= ?4.3082(9) ?, b ?= ?15.399(3) ? and c ?= ?19.689(4) ?. The crystal structure contains a three-dimensional framework of Sb squares and ribbons that extend along the a axis, including complex Sb–Sb bonding. La6Pd2.28Sb15 is diamagnetic, with a magnetic susceptibility weakly dependent on temperature (T). The resistivity (ρ) decreases when lowering the temperature, indicating metallic behavior, and at low temperatures ρ depends quadratically on T. Interestingly, both the Hall resistivity and magnetoresistance present a nonlinear dependence on the applied magnetic field, suggesting a multiband behavior. This is supported by density-functional electronic structure calculations which show a complex Fermi surface originated in the antimonide substructures and containing both electron and hole pockets as well as open sheets.
New ternary La2Sb-type compounds, ScRESb (RE = La, Ce, Pr, Nd, Sm, Tb), and the oxygen stuffed variant Sc4Yb4Sb 4O
Nuss, Juergen,Jansen, Martin
, p. 713 - 718 (2014/04/17)
Scandium rare-earth metal antimonides, ScRESb (RE = La, Ce, Pr, Nd, Sm, Tb) were synthesized from scandium metal and binary RESb at 1770 K in tantalum ampoules. According to X-ray analyses of the crystal structures, they adopt the tetragonal ScCeSi-type of structure (space group I4/mmm, Pearson code tI12), a variant of La2Sb, with a fully ordered atom distribution. Especially in ScSmSb and ScTbSb, the scandium atoms are distorted from an ideal 4 4 net in a way to form Sc nets of squares and rhombi in order to adjust to the lattice shrinkage in the ab plane, caused by the lanthanide contraction. Finally the structure changes from La2Sb to Sc 2Sb-type (anti-PbFCl-type), when terbium is replaced by dysprosium. The respective compound with ytterbium was only found when stoichiometric amounts of oxygen were present, resulting in Sc4Yb4Sb 4O, a La2Sb-type variant stuffed with oxygen. A structure field map, based on specific geometric parameters, easily allows for distinguishing between oxygen stuffed and oxygen-free compounds. Magnetic susceptibility measurements of ScCeSb, ScPrSb, and ScNdSb indicate Curie-Weiss behavior with ferromagnetic exchange coupling underlying. The magnetic moments correspond to the expected values for RE3+. Copyright
