Crystal growth and physical properties of Ln sub(2)MGa sub(12) (Ln=Pr, Nd, and Sm; M=Ni, Cu)

Single crystals of the Ln sub(2)MGa sub(12) (Ln=Pr, Nd, and Sm; M=Ni, Cu) family of compounds have been synthesized using Ga flux and characterized by single crystal X-ray diffraction. These phases are isostructural to Sm sub(2)NiGa sub(12) and crystallize in the tetragonal P4/nbm (no. 125, origin choice 2) space group, with Z=2 and lattice parameters a[inline image]6.0 Aa and c[inline image]15.3 Aa. These compounds order antiferromagnetically, and metallic behavior is observed in temperature ranges above the ordering temperature for each compound. Sm sub(2)CuGa sub(12) shows large positive magnetoresistance [inline image]130% in field up to 9 T.