Na2SiO8 crystallizes in the triclinic P-1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(5), one O(7), one O(8), and two equivalent O(3) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(5), one O(6), one O(7), one O(8), and two equivalent O(4) atoms. Si(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Si(1), and one O(7) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Si(1) and one O(8) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Na(1) and one Si(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Na(2) and one Si(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), one O(6), and one O(8) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Na(2) and one O(5) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), and one O(1) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one O(2), and one O(5) atom.
Na2SiO8 crystallizes in the triclinic P-1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(5), one O(7), one O(8), and two equivalent O(3) atoms. The Na(1)-O(1) bond length is 2.38 Å. The Na(1)-O(5) bond length is 2.80 Å. The Na(1)-O(7) bond length is 2.67 Å. The Na(1)-O(8) bond length is 2.68 Å. There is one shorter (2.25 Å) and one longer (2.27 Å) Na(1)-O(3) bond length. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(5), one O(6), one O(7), one O(8), and two equivalent O(4) atoms. The Na(2)-O(5) bond length is 2.70 Å. The Na(2)-O(6) bond length is 2.65 Å. The Na(2)-O(7) bond length is 2.40 Å. The Na(2)-O(8) bond length is 2.82 Å. There is one shorter (2.33 Å) and one longer (2.34 Å) Na(2)-O(4) bond length. Si(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. The Si(1)-O(1) bond length is 1.78 Å. The Si(1)-O(2) bond length is 1.83 Å. The Si(1)-O(3) bond length is 1.57 Å. The Si(1)-O(4) bond length is 1.58 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Si(1), and one O(7) atom. The O(1)-O(7) bond length is 1.36 Å. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Si(1) and one O(8) atom. The O(2)-O(8) bond length is 1.33 Å. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Na(1) and one Si(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Na(2) and one Si(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), one O(6), and one O(8) atom. The O(5)-O(6) bond length is 1.24 Å. The O(5)-O(8) bond length is 2.02 Å. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Na(2) and one O(5) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), and one O(1) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one O(2), and one O(5) atom.