Structure, and magnetic and transport behavior of twinned Ce2Rh3(Pb,Bi)(5)

摘要

Single crystals of a new compound, Ce2Rh3(Pb,Bi)(5), have been grown via a flux-growth technique using molten Ph as a solvent. The compound has been characterized by single crystal X-ray diffraction and found to be of the orthorhombic Y2Rh3Sn5 structure type [Cmc2(1) (No. 36), Z = 4] with lattice parameters a = 4.5980(2), b = 27.1000(17) and c = 7.4310(4) angstrom, with V = 925.95(9) angstrom(3). Ce2Rh3(Pb,Bi)(5) has a complex crystal structure containing Cc atoms encased in Rh-X (X = Pb/Bi) pentagonal and octagonal channels in [100], with polyanions similar to those found in Ce2Au3In5 and Yb2Pt3Sn5- Magnetization measurements find that Ce2Rh3(Pb,Bi)(5) is a quasi-two-dimensional system, where the Cc moments are spatially well-localized. Heat capacity measurements show a transition at the Neel temperature of 1.5K. Evidence for Fermi surface nesting is found in electrical resistivity measurements, and we argue that Ce2Rh3(Pb,Bi)(5) is very near a metal-insulator transition in zero field. (C) 2007 Elsevier Inc. All rights reserved.