High-pressure synthesis and characterizations of a new ternary Ce-based compound Ce3TiAs5

We report the structure and properties of a new Ce-based compound Ce3TiAs5 synthesized under high-pressure and high-temperature conditions. It crystallizes in a hexagonal Hf5Sn3Cu-anti type structure with zig-zag like Ce chains along the c axis. This compound is metallic and undergoes a magnetic phase transition at TN=13 K. A metamagnetic transition occurs at ~0.7 T. The Sommerfeld coefficient for the compound is determined to be about 215 mJ/(Ce-mol*K2), demonstrating a heavy Fermion behavior. The resistivity is featured with two humps, which arises from the synergistic effect of crystal electric field (CEF) and magnetic scattering. The magnetic ordering temperature TN gradually increases in the sequence of Ce3TiPn5 with Pn=Bi, Sb, and As, which implies that the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction should be still predominant in Ce3TiAs5.