A dense TiS3 sample has been processed by Spark Plasma Sintering. The structural analysis, obtained by coupling powder X-ray diffraction and transmission electron microscopy (TEM), shows that the A-variant of the ZrSe3-type structure is stabilized for the first time. Defects along the main atomic layer stacking directions are evidenced by high-resolution TEM, which explain the peculiar X-ray powder diffraction patterns, with strongly anisotropic microstrains. The presence of these structural defects might explain the existence of a metal-to-insulator transition with a charge localization below T MI ≈ 325 K. Large absolute values of the Seebeck coefficient, in the range −700 ≤ S ≤ −600 μV·K–1, are observed for 100 ≤ T ≤ 600 K, together with a low thermal conductivity, κ = 2 W·K–1·m–1 at 600 K. The T –1 dependence of the lattice part of κ indicates its phononic character. As the charge carrier concentration measured by Hall effect is too low, n = 1.24 × 1018 cm–3, extra doping would be necessary to decrease its too high electrical resistivity (ρ300K ∼ 1.4 Ω·cm) for thermoelectric applications.

Single-phase polycrystalline samples of the compounds MRh(6)B(3) (M = Fe, Co) as well as single crystals of CoRh(6)B(3) have been synthesized by arc-melting the elements under a purified argon atmosphere in a water-cooled copper crucible. The characterization of the new phases was achieved by using single-crystal and powder X-ray diffraction as well as EDX measurements. The two phases are isotypic and crystallize in the hexagonal Th(7)Fe(3) structure type (space group P6(3)mc, no. 186, Z = 2). In this structure, the magnetically active atoms (Fe, Co) are preferentially found on only one of the three available rhodium sites, and together with rhodium they build a three-dimensional network of interconnected (Rh/M)(3) triangles. Magnetic properties investigations show that both phases order ferromagnetically below Curie temperatures of 240 K (for FeRh(6)B(3)) and 150 K (for CoRh(6)B(3)). First-principles DFT calculations correctly reproduce not only the lattice parameters but also the ground state magnetic ordering in the two phases. These calculations also show that the long-range magnetic ordering in both phases occurs via indirect ferromagnetic coupling between the iron atoms mediated by rhodium. This magnetic structural model also predicts the saturation magnetizations to be 4.02 μ(B) for FeRh(6)B(3) (3.60 μ(B) found experimentally) and 2.75 μ(B) for CoRh(6)B(3). Furthermore, both phases are predicted to be metallic conductors as expected for these intermetallic borides.

Powder samples and single crystals of the borides M0.5Ru6.5B3 (M = Cr, Mn, Co, Ni) were synthesized by arc‐melting the elements in a water‐cooled copper crucible under argon. The new phases were structurally characterized by single‐crystal and powder X‐ray diffraction as well as EDX‐Analyses. They crystallize in the hexagonal Th7Fe3 structure type (space group P63mc, no. 186, Z = 2) and a pronounced site preferential M/Ru substitution is observed. Magnetic properties of the compounds were investigated and Pauli paramagnetism was observed in all cases. However, a strong temperature dependency is subsequently observed in Mn0.5Ru6.5B3 below 250 K, but no hint of magnetic ordering was found.

The title compounds are synthesized by arc‐melting of the elements and characterized by powder XRD and single crystal XRD of Cr0.78Rh6.22B3 and Mn0.39Rh6.61B3.