Authors: Pospíšil, M. Míšek, M. Diviš, M. Dušek, F.R. de Boer, L. Havela, J. Custers
J. Alloys Comp. 823 (2020) 153485.
Abstract: A new U-based compound of the U2Rh2Pb, a new compound of the U2T2X series (T – transition metal, X – Sn, In, Pb), was prepared in a single-crystal form. Its structure was determined as belonging to the tetragonal Mo2FeB2 structure type with the shortest U–U spacing along the c-axis. The crystals were subjected to study of magnetic, specific heat, and electrical resistivity in various magnetic fields. U2Rh2Pb undergoes an antiferromagnetic transition at a Néel temperature TN of 20 K and exhibits an enhanced Sommerfeld coefficient γ ≈ 150 mJ/molK2. In contrast to the two rhodium analogues U2Rh2In and U2Rh2Sn, the easy-magnetization direction is the c-axis with rather low value of the critical field Hc = 4.3 T of the metamagnetic transition of a spin-flip type. The observed dependences of TN and Hc on temperature and magnetic field have been used for constructing a magnetic phase diagram. The experimental observations are mostly supported by first-principles calculations.