New 4234-type compounds, structurally related to the n = 4 member of the (LnC)nNi2B2 homologous series of intermetallic borocarbides, were synthesized by arc-melting. Here we report that this structure type, previously observed only for Ni-based compounds, can be synthesized for a large number of transition elements. Further, we find it to be stable for medium through small lanthanides. The compounds have formulas Y4T2B3C4 [T = Fe, Co, Ni, Ru, Rh, and Ir], Ln4T2B3C4 [Ln = Er, Dy, and Gd; T = Fe and Co], Lu4Ni2B3C4, and Sc4Ni2B3C4. The unit cells are pseudo-tetragonal, with lattice parameters ranging from a = 3.348(1) Å, c = 25.90(1) Å for Sc4Ni2B3C4 to a = 3.624(1) Å, c = 26.63(1) Å for Y4Rh2B3C4. Structural investigation by exit-wave reconstruction is reported, showing the presence of twinning on the unit cell scale. The phases show either Curie-Weiss behavior with very small magnetic moments per transition metalatom or temperature-independent paramagnetism.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry