Na2ZrSi4H4O13 crystallizes in the monoclinic P2_1/c space group. Na(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and one O(6) atom. Zr(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form ZrO6 octahedra that share corners with two equivalent Si(2)O4 tetrahedra and corners with four equivalent Si(1)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Zr(1)O6 octahedra and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-44°. In the second Si site, Si(2) is bonded to one O(3), one O(5), one O(6), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Zr(1)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(4) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(4) atom. There are seven inequivalent O sites. In the first O site, O(4) is bonded in a distorted water-like geometry to one Na(1), one H(1), and one H(2) atom. In the second O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Si(1) and one Si(2) atom. In the third O site, O(6) is bonded in a 3-coordinate geometry to one Na(1), one Si(1), and one Si(2) atom. In the fourth O site, O(7) is bonded in a linear geometry to two equivalent Si(2) atoms. In the fifth O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Zr(1), and one Si(1) atom. In the sixth O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Zr(1), and one Si(1) atom. In the seventh O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Zr(1), and one Si(2) atom.
Na2ZrSi4H4O13 crystallizes in the monoclinic P2_1/c space group. Na(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and one O(6) atom. The Na(1)-O(1) bond length is 2.48 Å. The Na(1)-O(2) bond length is 2.42 Å. The Na(1)-O(3) bond length is 2.41 Å. The Na(1)-O(4) bond length is 2.32 Å. The Na(1)-O(6) bond length is 2.48 Å. Zr(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form ZrO6 octahedra that share corners with two equivalent Si(2)O4 tetrahedra and corners with four equivalent Si(1)O4 tetrahedra. Both Zr(1)-O(1) bond lengths are 2.14 Å. Both Zr(1)-O(2) bond lengths are 2.09 Å. Both Zr(1)-O(3) bond lengths are 2.13 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(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Zr(1)O6 octahedra and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-44°. The Si(1)-O(1) bond length is 1.63 Å. The Si(1)-O(2) bond length is 1.62 Å. The Si(1)-O(5) bond length is 1.68 Å. The Si(1)-O(6) bond length is 1.67 Å. In the second Si site, Si(2) is bonded to one O(3), one O(5), one O(6), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Zr(1)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. The Si(2)-O(3) bond length is 1.62 Å. The Si(2)-O(5) bond length is 1.66 Å. The Si(2)-O(6) bond length is 1.64 Å. The Si(2)-O(7) bond length is 1.63 Å. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(4) atom. The H(1)-O(4) bond length is 0.99 Å. In the second H site, H(2) is bonded in a single-bond geometry to one O(4) atom. The H(2)-O(4) bond length is 0.98 Å. There are seven inequivalent O sites. In the first O site, O(4) is bonded in a distorted water-like geometry to one Na(1), one H(1), and one H(2) atom. In the second O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Si(1) and one Si(2) atom. In the third O site, O(6) is bonded in a 3-coordinate geometry to one Na(1), one Si(1), and one Si(2) atom. In the fourth O site, O(7) is bonded in a linear geometry to two equivalent Si(2) atoms. In the fifth O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Zr(1), and one Si(1) atom. In the sixth O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Zr(1), and one Si(1) atom. In the seventh O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Zr(1), and one Si(2) atom.