Die Kristallstruktur von YbFe₂O₄

Abstract

The crystal structure of YbFe 2 O 4 was determined and refined by the x-ray method. This compound crystallizes trigonal in the space group R [unk] m with the unit-cell dimensions a = 3.455 ± 0.001, c = 25.054 ± 0.010 Å. The unit cell contains three formula units. The structure consists of the alternating layers of YbO 3/2 and Fe 2+ Fe 3+ O 5/2 . The oxygen ions are arranged like a sort of closest packing of spheres. The Yb ion is surrounded by six oxygen ions octahedrally, the Fe ion by five oxygen ions forming a trigonal bipyramid. This structure presents a new structure type for the AB 2 X 4 compound.