SEARCH · Engineering Papers
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
PrNi crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Pr is bonded in a 7-coordinate geometry to seven equivalent Ni atoms. There are a spread of Pr–Ni bond distances ranging from 2.95–3.12 Å. Ni is bonded in a 9-coordinate geometry to seven equivalent Pr and two equivalent Ni atoms. Both Ni–Ni bond lengths are 2.65 Å.
PrNi2 is Cubic Laves structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to twelve equivalent Ni atoms. All Pr–Ni bond lengths are 3.04 Å. Ni is bonded to six equivalent Pr and six equivalent Ni atoms to form a mixture of edge, face, and corner-sharing NiPr6Ni6 cuboctahedra. All Ni–Ni bond lengths are 2.60 Å.
PrNi5 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Pr is bonded in a 6-coordinate geometry to eighteen Ni atoms. There are six shorter (2.87 Å) and twelve longer (3.18 Å) Pr–Ni bond lengths. There are two inequivalent Ni sites. In the first Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Pr and six equivalent Ni atoms. All Ni–Ni bond lengths are 2.45 Å. In the second Ni site, Ni is bonded to four equivalent Pr and eight Ni atoms to form a mixture of corner, edge, and face-sharing NiPr4Ni8 cuboctahedra. All Ni–Ni bond lengths are 2.49 Å.
Pr3Ni is Cementite structured and crystallizes in the orthorhombic Pnma space group. The structure is two-dimensional and consists of two Pr3Ni sheets oriented in the (0, 0, 1) direction. there are two inequivalent Pr sites. In the first Pr site, Pr is bonded in a distorted L-shaped geometry to two equivalent Ni atoms. There are one shorter (2.83 Å) and one longer (2.95 Å) Pr–Ni bond lengths. In the second Pr site, Pr is bonded in a distorted bent 150 degrees geometry to two equivalent Ni atoms. There are one shorter (2.85 Å) and one longer (2.97 Å) Pr–Ni bond lengths. Ni is bonded in a 6-coordinate geometry to six Pr atoms.
PrNi3 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Pr sites. In the first Pr site, Pr is bonded in a distorted hexagonal planar geometry to eighteen Ni atoms. There are six shorter (2.90 Å) and twelve longer (3.22 Å) Pr–Ni bond lengths. In the second Pr site, Pr is bonded in a 12-coordinate geometry to twelve Ni atoms. There are a spread of Pr–Ni bond distances ranging from 2.90–3.19 Å. There are three inequivalent Ni sites. In the first Ni site, Ni is bonded to six equivalent Pr and six equivalent Ni atoms to form NiPr6Ni6 cuboctahedra that share corners with twelve equivalent NiPr5Ni7 cuboctahedra, edges with six equivalent NiPr6Ni6 cuboctahedra, and faces with eighteen equivalent NiPr5Ni7 cuboctahedra. All Ni–Ni bond lengths are 2.59 Å. In the second Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Pr and six equivalent Ni atoms. There are three shorter (2.46 Å) and three longer (2.50 Å) Ni–Ni bond lengths. In the third Ni site, Ni is bonded to five Pr and seven Ni atoms to form NiPr5Ni7 cuboctahedra that share corners with seventeen NiPr6Ni6 cuboctahedra, edges with eight equivalent NiPr5Ni7 cuboctahedra, and faces with fourteen NiPr6Ni6 cuboctahedra. There are two shorter (2.50 Å) and two longer (2.52 Å) Ni–Ni bond lengths.