PrSiAs3 crystallizes in the orthorhombic Pna2_1 space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 9-coordinate geometry to one As(6), two equivalent As(1), two equivalent As(2), two equivalent As(3), and two equivalent As(4) atoms. In the second Pr site, Pr(2) is bonded in a 9-coordinate geometry to one As(5), two equivalent As(1), two equivalent As(2), two equivalent As(3), and two equivalent As(4) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one As(2), one As(6), and two equivalent As(5) atoms to form corner-sharing SiAs4 tetrahedra. In the second Si site, Si(2) is bonded to one As(1), one As(5), and two equivalent As(6) atoms to form corner-sharing SiAs4 tetrahedra. There are six inequivalent As sites. In the first As site, As(5) is bonded in a distorted rectangular see-saw-like geometry to one Pr(2), one Si(2), and two equivalent Si(1) atoms. In the second As site, As(6) is bonded in a distorted rectangular see-saw-like geometry to one Pr(1), one Si(1), and two equivalent Si(2) atoms. In the third As site, As(1) is bonded to two equivalent Pr(1), two equivalent Pr(2), and one Si(2) atom to form a mixture of distorted edge and corner-sharing AsPr4Si trigonal bipyramids. In the fourth As site, As(2) is bonded to two equivalent Pr(1), two equivalent Pr(2), and one Si(1) atom to form a mixture of distorted edge and corner-sharing AsPr4Si trigonal bipyramids. In the fifth As site, As(3) is bonded in a distorted hexagonal planar geometry to two equivalent Pr(1), two equivalent Pr(2), and two equivalent As(4) atoms. In the sixth As site, As(4) is bonded in a 6-coordinate geometry to two equivalent Pr(1), two equivalent Pr(2), and two equivalent As(3) atoms.
PrSiAs3 crystallizes in the orthorhombic Pna2_1 space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 9-coordinate geometry to one As(6), two equivalent As(1), two equivalent As(2), two equivalent As(3), and two equivalent As(4) atoms. The Pr(1)-As(6) bond length is 3.18 Å. There is one shorter (3.12 Å) and one longer (3.18 Å) Pr(1)-As(1) bond length. There is one shorter (3.07 Å) and one longer (3.11 Å) Pr(1)-As(2) bond length. There is one shorter (3.31 Å) and one longer (3.37 Å) Pr(1)-As(3) bond length. There is one shorter (3.32 Å) and one longer (3.34 Å) Pr(1)-As(4) bond length. In the second Pr site, Pr(2) is bonded in a 9-coordinate geometry to one As(5), two equivalent As(1), two equivalent As(2), two equivalent As(3), and two equivalent As(4) atoms. The Pr(2)-As(5) bond length is 3.16 Å. There is one shorter (3.07 Å) and one longer (3.10 Å) Pr(2)-As(1) bond length. There is one shorter (3.07 Å) and one longer (3.12 Å) Pr(2)-As(2) bond length. There is one shorter (3.14 Å) and one longer (3.26 Å) Pr(2)-As(3) bond length. There is one shorter (3.13 Å) and one longer (3.30 Å) Pr(2)-As(4) bond length. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one As(2), one As(6), and two equivalent As(5) atoms to form corner-sharing SiAs4 tetrahedra. The Si(1)-As(2) bond length is 2.34 Å. The Si(1)-As(6) bond length is 2.38 Å. There is one shorter (2.36 Å) and one longer (2.39 Å) Si(1)-As(5) bond length. In the second Si site, Si(2) is bonded to one As(1), one As(5), and two equivalent As(6) atoms to form corner-sharing SiAs4 tetrahedra. The Si(2)-As(1) bond length is 2.34 Å. The Si(2)-As(5) bond length is 2.38 Å. There is one shorter (2.36 Å) and one longer (2.40 Å) Si(2)-As(6) bond length. There are six inequivalent As sites. In the first As site, As(5) is bonded in a distorted rectangular see-saw-like geometry to one Pr(2), one Si(2), and two equivalent Si(1) atoms. In the second As site, As(6) is bonded in a distorted rectangular see-saw-like geometry to one Pr(1), one Si(1), and two equivalent Si(2) atoms. In the third As site, As(1) is bonded to two equivalent Pr(1), two equivalent Pr(2), and one Si(2) atom to form a mixture of distorted edge and corner-sharing AsPr4Si trigonal bipyramids. In the fourth As site, As(2) is bonded to two equivalent Pr(1), two equivalent Pr(2), and one Si(1) atom to form a mixture of distorted edge and corner-sharing AsPr4Si trigonal bipyramids. In the fifth As site, As(3) is bonded in a distorted hexagonal planar geometry to two equivalent Pr(1), two equivalent Pr(2), and two equivalent As(4) atoms. There is one shorter (2.57 Å) and one longer (2.59 Å) As(3)-As(4) bond length. In the sixth As site, As(4) is bonded in a 6-coordinate geometry to two equivalent Pr(1), two equivalent Pr(2), and two equivalent As(3) atoms.