DOE OSTI2020
SrAu3In3 crystallizes in the orthorhombic Pmmn space group. The structure is three-dimensional. Sr is bonded in a 12-coordinate geometry to eight Au and six equivalent In atoms. There are a spread of Sr–Au bond distances ranging from 3.43–3.73 Å. There are four shorter (3.65 Å) and two longer (3.90 Å) Sr–In bond lengths. There are two inequivalent Au sites. In the first Au site, Au is bonded in a 1-coordinate geometry to three equivalent Sr, two equivalent Au, and four In atoms. Both Au–Au bond lengths are 2.86 Å. There are a spread of Au–In bond distances ranging from 2.76–2.99 Å. In the second Au site, Au is bonded in a 9-coordinate geometry to two equivalent Sr and seven In atoms. There are a spread of Au–In bond distances ranging from 2.83–2.98 Å. There are two inequivalent In sites. In the first In site, In is bonded to three equivalent Sr and four Au atoms to form distorted InSr3Au4 tetrahedra that share corners with two equivalent InAu7 hexagonal pyramids, corners with four equivalent InSr3Au4 tetrahedra, edges with two equivalent InAu7 hexagonal pyramids, edges with six equivalent InSr3Au4 tetrahedra, and faces with four equivalent InSr3Au4 tetrahedra. In the second In site, In is bonded to seven Au atoms to form distorted InAu7 hexagonal pyramids that share corners with four equivalent InSr3Au4 tetrahedra, edges with six equivalent InAu7 hexagonal pyramids, and edges with four equivalent InSr3Au4 tetrahedra.