CeAu2Bi: A new nonsymmorphic antiferromagnetic compound

Here, we report the structural and electronic properties of CeAu2Bi, a new heavy-fermion compound crystallizing in a nonsymmorphic hexagonal structure (P63/mmc). The Ce3+ ions form a triangular lattice which orders antiferromagnetically below TN=3.1K with a magnetic hard axis along the c axis. Under applied pressure, TN increases linearly at a rate of 0.07K/kbar, indicating that the Ce f electrons are fairly localized. In fact, heat capacity measurements provide an estimate of 150(10) mJ/molK2 for the Sommerfeld coefficient. The crystal-field scheme obtained from our thermodynamic data points to a ground state with a dominantly |jz=±1/2) character, which commonly occurs in systems with a hard c axis. Finally, electronic band structure calculations and symmetry analysis in k space reveal that CeAu2Bi hosts symmetry-protected crossings at kz=π in the paramagnetic state.