PrNiSi2 crystallizes in the orthorhombic Cmcm space group. Pr(1) is bonded in a 14-coordinate geometry to four equivalent Ni(1), four equivalent Si(1), and six equivalent Si(2) atoms. Ni(1) is bonded in a 9-coordinate geometry to four equivalent Pr(1), one Si(2), and four equivalent Si(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to four equivalent Pr(1) and four equivalent Ni(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to six equivalent Pr(1), one Ni(1), and two equivalent Si(2) atoms.
PrNiSi2 crystallizes in the orthorhombic Cmcm space group. Pr(1) is bonded in a 14-coordinate geometry to four equivalent Ni(1), four equivalent Si(1), and six equivalent Si(2) atoms. All Pr(1)-Ni(1) bond lengths are 3.17 Å. There are two shorter (3.10 Å) and two longer (3.15 Å) Pr(1)-Si(1) bond lengths. There are four shorter (3.11 Å) and two longer (3.21 Å) Pr(1)-Si(2) bond lengths. Ni(1) is bonded in a 9-coordinate geometry to four equivalent Pr(1), one Si(2), and four equivalent Si(1) atoms. The Ni(1)-Si(2) bond length is 2.32 Å. There are two shorter (2.32 Å) and two longer (2.37 Å) Ni(1)-Si(1) bond lengths. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to four equivalent Pr(1) and four equivalent Ni(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to six equivalent Pr(1), one Ni(1), and two equivalent Si(2) atoms. Both Si(2)-Si(2) bond lengths are 2.44 Å.