Experimental characterization reveals distinct magnetic ordering and topological states in Ln3TiBi5 crystals, highlighting candidates for magnetic topological materials.
Key Points
Synthesize single crystals of Ln3TiBi5 (Ln = Pr, Nd, Gd) to characterize their magnetic properties, electronic band structures, and chemical bonding mechanisms.
Grew single crystals of Pr3TiBi5, Nd3TiBi5, and Gd3TiBi5.
Conducted magnetic susceptibility and heat capacity measurements down to 2 K.
Performed density functional theory (DFT) calculations with spin-orbit coupling and crystal orbital Hamilton population (COHP) bonding analyses.
Pr3TiBi5 displays no magnetic ordering down to 2 K, whereas Nd3TiBi5 and Gd3TiBi5 show antiferromagnetic ordering at 6.2 K and ~18 K (17.1 K for H ∥ c and 18.8 K for H ⊥ c), respectively.
DFT calculations reveal topologically nontrivial states near the Fermi level in Gd3TiBi5, where spin-orbit coupling opens a local band gap along the M–K path.
COHP analysis identifies hypervalent Bi4d–Bi4d bonding within one-dimensional bismuth chains and determines that lanthanides form their strongest bonds with Bi6g.