Investigating the A_n+1B_nX_3n+1 Homologous Series: A New Platform for Studying Magnetic Praseodymium Based Intermetallics

Abstract

The recent discovery of the A n +1 B n X 3 n +1 (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 n +1 Co n Ge 3 n +1 ( n = 1, 4, 5, 6, and ∞) show evidence of heavy electron behavior with complex magnetic interactions. While the Ce analogues have been investigated, only n = 1, 2, and ∞ of Pr n +1 Co n Ge 3 n +1 have been synthesized, with n = 1 and 2 showing a nonsinglet magnetic ground state. The Pr analogues can provide a platform for direct comparison of highly correlated behavior. In this perspective, we discuss the impetus for synthesizing the Pr n +1 Co n Ge 3 n +1 members and present the structural characterization of the n = 3 and n = 4 members. We lay the foundation for future investigations of the Pr n +1 Co n Ge 3 n +1 family of compounds and highlight the importance of complementary methods to characterize new quantum materials.

Much more to explore with an oxidation state of nearly four: Pr valence instability in intermetallic m -Pr 2 Co 3 Ge 5

“…The remaining Sn flux was etched using 1:1 HCl:H 2 O, with a yield of approximately 80%. Almost all reactions produced members of the Pr n +1 Co n Ge 3 n +1 homologous series ( 56 ) as a side product, but this phase was easily removed because of its plate like morphology and size (~2 mm by ~2 mm). In addition, trace amounts of PrCoGe 3 are evident in high-resolution PXRD.…”