A New Superconductor Parent Compound NaMn₆Bi₅ with Quasi-One-Dimensional Structure and Lower Antiferromagnetic-Like Transition Temperatures

Mn-based superconductor is rare and recently reported in quasi-one-dimensional KMn$_6$Bi$_5$ with [Mn$_6$Bi$_5$]-columns under high pressure. Here we report the synthesis, magnetic properties, electrical resistivity, specific heat capacity of newly-discovered NaMn$_6$Bi$_5$ single crystal. Compared other AMn$_6$Bi$_5$ (A = K, Rb, Cs), has larger intra-column Bi-Bi bond length, which may result two decoupled antiferromagnetic transitions at 47.3 K 52.3 K. The relatively lower transition temperatures make a more suitable platform to explore superconductors. Anisotropic resistivity non-Fermi liquid behavior low temperature are observed. Heat measurement reveals that similar Debye those Rb), whereas Sommerfeld coefficient unusually large. Using first-principles calculations, quite different density states an unusual enhancement near Fermi level observed for NaMn$_6$Bi$_5$, when compared Cs) compounds.