DOE OSTI2020
Ni5Si2P3 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. there are five inequivalent Ni+1.80+ sites. In the first Ni+1.80+ site, Ni+1.80+ is bonded in a 6-coordinate geometry to four Si4- and two equivalent P+0.33- atoms. There are a spread of Ni–Si bond distances ranging from 2.36–2.47 Å. There are one shorter (2.21 Å) and one longer (2.34 Å) Ni–P bond lengths. In the second Ni+1.80+ site, Ni+1.80+ is bonded to six P+0.33- atoms to form a mixture of distorted face, edge, and corner-sharing NiP6 octahedra. The corner-sharing octahedra tilt angles range from 44–56°. There are a spread of Ni–P bond distances ranging from 2.24–2.44 Å. In the third Ni+1.80+ site, Ni+1.80+ is bonded in a 6-coordinate geometry to two equivalent Si4- and four P+0.33- atoms. There are one shorter (2.30 Å) and one longer (2.43 Å) Ni–Si bond lengths. There are a spread of Ni–P bond distances ranging from 2.22–2.71 Å. In the fourth Ni+1.80+ site, Ni+1.80+ is bonded in a 6-coordinate geometry to four equivalent Si4- and two equivalent P+0.33- atoms. There are a spread of Ni–Si bond distances ranging from 2.27–2.57 Å. There are one shorter (2.23 Å) and one longer (2.38 Å) Ni–P bond lengths. In the fifth Ni+1.80+ site, Ni+1.80+ is bonded in a 6-coordinate geometry to two equivalent Si4- and four P+0.33- atoms. There are one shorter (2.28 Å) and one longer (2.72 Å) Ni–Si bond lengths. There are a spread of Ni–P bond distances ranging from 2.22–2.39 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 7-coordinate geometry to six Ni+1.80+ and one P+0.33- atom. The Si–P bond length is 2.67 Å. In the second Si4- site, Si4- is bonded in a 7-coordinate geometry to six Ni+1.80+ and one P+0.33- atom. The Si–P bond length is 2.86 Å. There are three inequivalent P+0.33- sites. In the first P+0.33- site, P+0.33- is bonded in a 6-coordinate geometry to six Ni+1.80+ atoms. In the second P+0.33- site, P+0.33- is bonded in a 8-coordinate geometry to six Ni+1.80+ and two Si4- atoms. In the third P+0.33- site, P+0.33- is bonded in a 6-coordinate geometry to six Ni+1.80+ atoms.