Na2ZnSiO4 crystallizes in the monoclinic Pc space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted NaO4 tetrahedra that share corners with four equivalent Na(2)O4 tetrahedra, corners with four equivalent Zn(1)O4 tetrahedra, and corners with four equivalent Si(1)O4 tetrahedra. In the second Na site, Na(2) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form NaO4 tetrahedra that share corners with four equivalent Na(1)O4 tetrahedra, corners with four equivalent Zn(1)O4 tetrahedra, and corners with four equivalent Si(1)O4 tetrahedra. Zn(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form ZnO4 tetrahedra that share corners with four equivalent Na(1)O4 tetrahedra, corners with four equivalent Na(2)O4 tetrahedra, and corners with four equivalent Si(1)O4 tetrahedra. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share corners with four equivalent Na(1)O4 tetrahedra, corners with four equivalent Na(2)O4 tetrahedra, and corners with four equivalent Zn(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Zn(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Zn(1), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted trigonal pyramidal geometry to one Na(1), one Na(2), one Zn(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Zn(1), and one Si(1) atom.
Na2ZnSiO4 crystallizes in the monoclinic Pc space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted NaO4 tetrahedra that share corners with four equivalent Na(2)O4 tetrahedra, corners with four equivalent Zn(1)O4 tetrahedra, and corners with four equivalent Si(1)O4 tetrahedra. The Na(1)-O(1) bond length is 2.32 Å. The Na(1)-O(2) bond length is 2.33 Å. The Na(1)-O(3) bond length is 2.30 Å. The Na(1)-O(4) bond length is 2.33 Å. In the second Na site, Na(2) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form NaO4 tetrahedra that share corners with four equivalent Na(1)O4 tetrahedra, corners with four equivalent Zn(1)O4 tetrahedra, and corners with four equivalent Si(1)O4 tetrahedra. The Na(2)-O(1) bond length is 2.26 Å. The Na(2)-O(2) bond length is 2.30 Å. The Na(2)-O(3) bond length is 2.23 Å. The Na(2)-O(4) bond length is 2.26 Å. Zn(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form ZnO4 tetrahedra that share corners with four equivalent Na(1)O4 tetrahedra, corners with four equivalent Na(2)O4 tetrahedra, and corners with four equivalent Si(1)O4 tetrahedra. The Zn(1)-O(1) bond length is 1.96 Å. The Zn(1)-O(2) bond length is 1.97 Å. The Zn(1)-O(3) bond length is 1.94 Å. The Zn(1)-O(4) bond length is 1.95 Å. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share corners with four equivalent Na(1)O4 tetrahedra, corners with four equivalent Na(2)O4 tetrahedra, and corners with four equivalent Zn(1)O4 tetrahedra. The Si(1)-O(1) bond length is 1.63 Å. The Si(1)-O(2) bond length is 1.64 Å. The Si(1)-O(3) bond length is 1.63 Å. The Si(1)-O(4) bond length is 1.64 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Zn(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Zn(1), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted trigonal pyramidal geometry to one Na(1), one Na(2), one Zn(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Zn(1), and one Si(1) atom.