Scandium plumbides Sc2Ni2Pb, ScNi1.34Pb and ScCuPb

The crystal structures of three new Sc-based plumbides have been determined from the single-crystal X-ray diffraction data. Sc2Ni2Pb crystallizes with an orthorhombic structure of the Mn2AlB2 - type (space group Cmmm, No. 65, lattice parameters: а = 3.96386(18), b = 13.5551(6), с = 3.35576(11) Å, Z = 2, R1 = 0.0102, wR2 = 0.0249). ScNi1.34Pb forms with a cubic unit cell of the MnCu2Al - type (space group Fm-3m, No. 225, lattice parameter а = 6.25096(12) Å, Z = 4, R1 = 0.0066, wR2 = 0.0141). ScCuPb crystallizes with the hexagonal LiGaGe - type structure (space group P63mc, No. 186, lattice parameters: а = 4.4338(2), с = 6.9500(4) Å, Z = 2, R1 = 0.0383, wR2 = 0.0920). Low-temperature magnetic measurements have revealed that the compound Sc2Ni2Pb is a Pauli paramagnet with the molar magnetic susceptibility of about 2.4 × 10−4 emu/mole.