Crystal Growth and Properties of YbCuGa3: First Monoclinic System in the RETX3Family.

High quality single crystals of YbCuGa3wereobtainedfrom the reaction of Yb and Cu in excess liquid gallium as a solventat 1173 K. The crystal structure of YbCuGa3was refinedusing X-ray diffraction data on a selected high quality single crystal.YbCuGa3crystallizes in a new structure type in the monoclinicspace group C2/mand lattice constants a= 11.6891(8) Å, b= 4.162(4) Å, c= 8.3196(7) Å, and β = 110.834(5)°. Thecrystal structure of YbCuGa3is composed of eight cappedhexagonal prism cages [Yb4Cu4Ga12] occupying one ytterbium atom in each ring, which is shared throughthe edge Cu and Ga atoms along theabplane resultingin a three-dimensional network. The magnetic susceptibility of YbCuGa3was investigated in the temperature range 2–300 Kobeying the Curie–Weiss law above 130 K and the experimentallymeasured magnetic moment indicates mixed valent ytterbium and a deviationin inverse susceptibility data below 130 K. Electrical conductivitymeasurements show that the compound exhibits metallic nature. [ABSTRACT FROM AUTHOR]