Crystal Structure and Properties of Yb 5 Ni 4 Ge 10

The new compound Yb 5 Ni 4 Ge 10 was obtained as single crystals in high yield from reactions run in liquid indium. Single‐crystal X‐ray diffraction data showed that it crystallizes in the Sc 5 Co 4 Si 10 structure type in the tetragonal space group P 4/ mbm . The structure is a three‐dimensional framework of [Ni 4 Ge 10 ] atoms with voids filled by Yb atoms. The Ni and Ge atoms form pentagons, hexagons, and octagons along the ab one‐dimensional plane, which are interconnected along the c axis via Ni–Ge–Ni zigzag chains. Magnetic measurements reveal that Yb 5 Ni 4 Ge 10 crystals show paramagnetic behavior with a lack of long‐range magnetic ordering down to 2 K. The magnetic susceptibility deviates from the Curie–Weiss law below 100 K, presumably because of crystal field effects from Yb 3+ ions. In specific heat measurements, the compound exhibits non‐Fermi‐liquid‐like behavior at low temperatures.