Crystal structure of rare-earth-rich platinum pnictides RE5Pt2X (RE=Y, Gd, Tb, Dy, Ho, Er, Tm, Lu; X=Sb, Bi) and magnetic properties of Er5Pt2Bi

Fifteen new rare-earth antimonides and bismuthides RE5Pt2X (see Table 1) have been synthesized and characterized by X-ray powder methods. The compounds are isostructural to previously reported RE5M2X pnictides and adopt the Mo5B2Si structure (space group I4/mcm, an ordered version of Cr5B3). The RE5M2X series now includes 47 antimonides and bismuthides with M=Ni, Pd, Pt and the heavy rare earths except for ytterbium. Atomic and thermal parameters have been refined and the magnetic susceptibility was measured for Er5Pt2Bi.