DOE OSTI2020
HfZr(RhSb)2 is half-Heusler-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. Hf is bonded in a body-centered cubic geometry to four Rh and four Sb atoms. There are one shorter (2.74 Å) and three longer (2.82 Å) Hf–Rh bond lengths. There are one shorter (2.80 Å) and three longer (2.81 Å) Hf–Sb bond lengths. Zr is bonded in a body-centered cubic geometry to four Rh and four Sb atoms. There are one shorter (2.82 Å) and three longer (2.84 Å) Zr–Rh bond lengths. There are three shorter (2.83 Å) and one longer (2.85 Å) Zr–Sb bond lengths. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded to one Hf and three equivalent Zr atoms to form distorted RhHfZr3 tetrahedra that share corners with four equivalent SbHfZr3 tetrahedra, corners with twelve RhHfZr3 tetrahedra, and edges with six SbHf3Zr tetrahedra. In the second Rh site, Rh is bonded to three equivalent Hf and one Zr atom to form distorted RhHf3Zr tetrahedra that share corners with four equivalent SbHf3Zr tetrahedra, corners with twelve RhHfZr3 tetrahedra, and edges with six SbHf3Zr tetrahedra. There are two inequivalent Sb sites. In the first Sb site, Sb is bonded to three equivalent Hf and one Zr atom to form distorted SbHf3Zr tetrahedra that share corners with four equivalent RhHf3Zr tetrahedra, corners with twelve SbHf3Zr tetrahedra, and edges with six RhHfZr3 tetrahedra. In the second Sb site, Sb is bonded to one Hf and three equivalent Zr atoms to form distorted SbHfZr3 tetrahedra that share corners with four equivalent RhHfZr3 tetrahedra, corners with twelve SbHf3Zr tetrahedra, and edges with six RhHfZr3 tetrahedra.