Magnetic structure of ternary intermetallic Tb3Co4Sn13 with nonchiral crystal structure

Abstract

Single crystals of the ternary stannide Tb₃Co₄Sn₁₃ were synthesized using the tin self-flux method. This article reports the results of magnetic susceptibility, specific heat, and neutron diffraction studies. The title compound undergoes a structural phase transition at T_D of 89.4 K and a magnetic ordering temperature T_N of 11.3 K. The crystal structure transitions from a high-temperature Pm-3n structure to a rhombohedral R-3c structure, and this transition is accompanied by an increase in unit cell volume at T_D. Tb³⁺ is the only magnetic species in the compound, with spins entering long-range magnetic order states below T_N.​ The magnetic space group is R-3′c (#167.105), the maximal subgroup of the proposed R-3c structure. Also investigated was the isostructural Nd₃Co₄Sn₁₃. The same R-3c model fits the low-temperature structure of Nd₃Co₄Sn₁₃, and the magnetic space group is identified as R-3′c' (#167.106), consistent with the structure reported in the authors’ previous study.