Much more to explore with an oxidation state of nearly four: Pr valence instability in intermetallic -PrCoGe.

For some intermetallic compounds containing lanthanides, structural transitions can result in intermediate electronic states between trivalency and tetravalency; however, this is rarely observed for praseodymium compounds. The dominant trivalency of praseodymium limits potential discoveries of emergent quantum states in itinerant 4 systems accessible using Pr-based compounds. Here, we use in situ powder x-ray diffraction and in situ electron energy-loss spectroscopy (EELS) to identify an intermetallic example of a dominantly Pr state in the polymorphic system PrCoGe.

Investigating the A B X Homologous Series: A New Platform for Studying Magnetic Praseodymium Based Intermetallics.

The recent discovery of the A B X (A = lanthanide, B = transition metal, X = tetrel) homologous series provides a new platform to study the structure-property relationships of highly correlated electron systems. Several members of Ce Co Ge ( = 1, 4, 5, 6, and ∞) show evidence of heavy electron behavior with complex magnetic interactions. While the Ce analogues have been investigated, only = 1, 2, and ∞ of Pr Co Ge have been synthesized, with = 1 and 2 showing a nonsinglet magnetic ground state.

It Runs in the BaAl Family: Relating the Structure and Properties of Middle Child LnCoGe (Ln = Pr, Nd, and Sm) to its Siblings LnCoGe and LnCoGe.

The BaAl prototype structure and its derivatives have been identified to host several topological quantum materials and noncentrosymmetric superconductors. Single crystals up to ∼3 mm × 3 mm × 5 mm of LnCoGe (Ln = Pr, Nd, and Sm) are obtained via flux growth utilizing Sn as metallic flux. The crystal structure is isostructural to the LuCoSi structure type in the crystallographic space group 2/.