A new family of rare earth compounds,the ternary silicides RE2RhSi3 (RE = Y,La, Ce,Nd, Sm,Gd, Tb,Dy, Ho,Er) - crystal structure electrical and magnetic properties

New ternary silicides RE₂RhSi₃ (RE = Y, La, Ce, Nd, Sm, Gd, Tb, Dy, Ho, Er) have been prepared. They crystallize with a hexagonal symmetry structure which is derived from the AlB₂-type. Si and Rh atoms are inside RE₆ distorted trigonal prisms and are ordered in a two dimensional sublattice perpendicular to the c axis. The a and c parameters are approximately twice those of the corresponding disilicides RESi₂. La₂RhSi₃ and Y₂RhSi₃ are not superconducting down to 1.6 K. Nd₂RhSi₃ is ferromagnetic at 15 K, but the other silicides order antiferromagnetically with metamagnetic phase transitions for certain of them.