FeZnSiO5 crystallizes in the triclinic P1 space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(10), one O(2), one O(4), one O(5), one O(7), and one O(9) atom to form FeO6 octahedra that share corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 39°. In the second Fe site, Fe(2) is bonded to one O(1), one O(10), one O(3), one O(6), one O(8), and one O(9) atom to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 39°. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a 5-coordinate geometry to one O(10), one O(3), one O(4), one O(7), and one O(8) atom. In the second Zn site, Zn(2) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(5), one O(6), and one O(9) atom. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-46°. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-48°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Fe(2), one Zn(2), and one Si(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Fe(1), one Zn(2), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Fe(2), one Zn(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Fe(1), one Zn(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Fe(1), one Zn(2), and one Si(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Fe(2), one Zn(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Fe(1), one Zn(1), and one Si(1) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Fe(2), one Zn(1), and one Si(1) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Zn(2) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Zn(1) atom.
FeZnSiO5 crystallizes in the triclinic P1 space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(10), one O(2), one O(4), one O(5), one O(7), and one O(9) atom to form FeO6 octahedra that share corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 39°. The Fe(1)-O(10) bond length is 1.89 Å. The Fe(1)-O(2) bond length is 2.01 Å. The Fe(1)-O(4) bond length is 1.99 Å. The Fe(1)-O(5) bond length is 2.03 Å. The Fe(1)-O(7) bond length is 2.03 Å. The Fe(1)-O(9) bond length is 1.89 Å. In the second Fe site, Fe(2) is bonded to one O(1), one O(10), one O(3), one O(6), one O(8), and one O(9) atom to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 39°. The Fe(2)-O(1) bond length is 2.00 Å. The Fe(2)-O(10) bond length is 1.90 Å. The Fe(2)-O(3) bond length is 2.02 Å. The Fe(2)-O(6) bond length is 2.01 Å. The Fe(2)-O(8) bond length is 2.01 Å. The Fe(2)-O(9) bond length is 1.90 Å. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a 5-coordinate geometry to one O(10), one O(3), one O(4), one O(7), and one O(8) atom. The Zn(1)-O(10) bond length is 1.93 Å. The Zn(1)-O(3) bond length is 2.17 Å. The Zn(1)-O(4) bond length is 2.42 Å. The Zn(1)-O(7) bond length is 2.01 Å. The Zn(1)-O(8) bond length is 2.02 Å. In the second Zn site, Zn(2) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(5), one O(6), and one O(9) atom. The Zn(2)-O(1) bond length is 2.31 Å. The Zn(2)-O(2) bond length is 2.27 Å. The Zn(2)-O(5) bond length is 1.99 Å. The Zn(2)-O(6) bond length is 2.05 Å. The Zn(2)-O(9) bond length is 1.93 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-46°. The Si(1)-O(1) bond length is 1.64 Å. The Si(1)-O(2) bond length is 1.64 Å. The Si(1)-O(7) bond length is 1.66 Å. The Si(1)-O(8) bond length is 1.67 Å. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-48°. The Si(2)-O(3) bond length is 1.64 Å. The Si(2)-O(4) bond length is 1.64 Å. The Si(2)-O(5) bond length is 1.66 Å. The Si(2)-O(6) bond length is 1.67 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Fe(2), one Zn(2), and one Si(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Fe(1), one Zn(2), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Fe(2), one Zn(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Fe(1), one Zn(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Fe(1), one Zn(2), and one Si(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Fe(2), one Zn(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Fe(1), one Zn(1), and one Si(1) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Fe(2), one Zn(1), and one Si(1) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Zn(2) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Zn(1) atom.