New Polar Intermetallic Phases RE(2)Zn(5)Tt (RE = La-Nd; Tt = Sn and Pb): Synthesis, Structure, Chemical Bonding, and Magnetic Properties

作者：Suen Nian Tzu; Bobev Svilen^*

来源：Inorganic Chemistry, 2013, 52(15): 9102-9110.

DOI：10.1021/ic401339v

Reported are the synthesis, crystal structure, electronic structure, and magnetic properties of a series of zinc-rich ternary phases with formulas RE(2)Zn(5)Tt (RE = La-Nd; Tt = Sn and Pb). The structures of these compounds have been established by single-crystal and powder X-ray diffraction. They crystallize in the orthorhombic space group Cmcm (No. 63, LaRhSn2 structure type, Pearson symbol oC32). The most prominent structural feature is the trigonal-planar coordination of the Sn(Pb) atoms; the latter interconnect layers of Zn atoms to comprise a complex [Zn(5)Tt] polyanionic framework. The structural relationships between the structure of the title compounds and the EuIn4, La3Al11, and YIrGe2 structure types are highlighted. Temperature-dependent DC magnetization measurements indicate Pauli-like paramagnetism for La2Zn5Sn, while Ce2Zn5Sn, Pr2Zn5Sn, and Nd2Zn5Sn display Curie-Weiss behavior in the high temperature regime. At cryogenic temperatures, the magnetic responses of Ce2Zn5Sn, Pr(2)Zn5(S)n, and Nd2Zn5Sn appear to deviate from the Curie-Weiss law; however, no magnetic orderings could be observed down to 5 K Theoretical considerations of the electronic structure on the basis of the tight-binding linear muffin tin orbital (TB-LMTO-ASA) method are also presented and discussed.

• 出版日期2013-8-5