A New Superconductor Parent Compound NaMn_(6)Bi_(5) with Quasi-One-Dimensional Structure and Lower Antiferromagnetic-Like Transition Temperatures

Mn-based superconductors are very rare and their superconductivity has only been reported in three-dimensional Mn P and quasi-one-dimensional KMn_(6)Bi_(5) and Rb Mn_(6)Bi_(5) with[Mn_(6)Bi_(5)]-columns under high pressures.Here we report the synthesis,magnetism,electrical resistivity,and specific heat capacity of the newly discovered quasione-dimensional Na Mn_(6)Bi_(5).Compared with other AMn_(6)Bi_(5)(A=K,Rb,and Cs),Na Mn_(6)Bi_(5) has abnormal Bi–Bi bond lengths and two antiferromagnetic-like transitions at 47.3 K and 51.8 K.Anisotropic resistivity and low-temperature non-Fermi liquid behavior are observed.Heat capacity measurement reveals that the Sommerfeld coefficient for Na Mn_(6)Bi_(5) is unusually large.Using first-principles calculations,an unusual enhancement of density of states near the Fermi level is demonstrated for Na Mn_(6)Bi_(5).The features make Na Mn_(6)Bi_(5) a more suitable platform to explore the interplay of magnetism and superconductivity.